diff --git a/MODULE.bazel b/MODULE.bazel index 81f16b7b9e..452aea3e3f 100644 --- a/MODULE.bazel +++ b/MODULE.bazel @@ -275,6 +275,14 @@ crate.annotation( inject_repo(crate, "zlib") +crate.annotation( + build_script_env = { + "LIBSQLITE3_FLAGS": "SQLITE_ENABLE_DBPAGE_VTAB", + }, + crate = "libsqlite3-sys", + gen_build_script = "on", +) + bazel_dep(name = "xz", version = "5.4.5.bcr.8") single_version_override( module_name = "xz", diff --git a/codex-rs/.cargo/config.toml b/codex-rs/.cargo/config.toml index 8a6f2c11ee..57f3af18cd 100644 --- a/codex-rs/.cargo/config.toml +++ b/codex-rs/.cargo/config.toml @@ -1,3 +1,6 @@ +[env] +LIBSQLITE3_FLAGS = "SQLITE_ENABLE_DBPAGE_VTAB" + [target.'cfg(all(windows, target_env = "msvc"))'] rustflags = ["-C", "link-arg=/STACK:8388608", "-C", "target-feature=+crt-static"] diff --git a/codex-rs/Cargo.lock b/codex-rs/Cargo.lock index c13f25c84b..40e4608d22 100644 --- a/codex-rs/Cargo.lock +++ b/codex-rs/Cargo.lock @@ -3680,11 +3680,13 @@ name = "codex-state" version = "0.0.0" dependencies = [ "anyhow", + "cc", "chrono", "clap", "codex-git-utils", "codex-protocol", "dirs", + "libsqlite3-sys", "log", "owo-colors", "pretty_assertions", diff --git a/codex-rs/Cargo.toml b/codex-rs/Cargo.toml index ec38a87cff..c7c62f655a 100644 --- a/codex-rs/Cargo.toml +++ b/codex-rs/Cargo.toml @@ -260,6 +260,7 @@ axum = { version = "0.8", default-features = false } base64 = "0.22.1" bm25 = "2.3.2" bytes = "1.10.1" +cc = "1.2.55" chardetng = "0.1.17" chrono = "0.4.43" clap = "4" @@ -306,6 +307,7 @@ keyring = { version = "3.6", default-features = false } landlock = "0.4.4" lazy_static = "1" libc = "0.2.182" +libsqlite3-sys = "0.30.1" log = "0.4" lru = "0.16.3" maplit = "1.0.2" diff --git a/codex-rs/cli/src/state_db_recovery.rs b/codex-rs/cli/src/state_db_recovery.rs index 7aeffaca3a..a869e675b2 100644 --- a/codex-rs/cli/src/state_db_recovery.rs +++ b/codex-rs/cli/src/state_db_recovery.rs @@ -18,7 +18,9 @@ pub(crate) fn is_locked(detail: &str) -> bool { pub(crate) fn confirm_repair(startup_error: &LocalStateDbStartupError) -> std::io::Result { eprintln!("Codex couldn't start because its local database appears to be damaged."); - eprintln!("Codex can try a safe repair by backing up those files and rebuilding them."); + eprintln!( + "Codex can try a last-resort startup repair by backing up those files and rebuilding empty local databases." + ); print_technical_details(startup_error); crate::confirm("Repair Codex local data now? [y/N]: ") } diff --git a/codex-rs/state/BUILD.bazel b/codex-rs/state/BUILD.bazel index b3f0fecab7..ec952cbad5 100644 --- a/codex-rs/state/BUILD.bazel +++ b/codex-rs/state/BUILD.bazel @@ -3,5 +3,6 @@ load("//:defs.bzl", "codex_rust_crate") codex_rust_crate( name = "state", crate_name = "codex_state", + build_script_data = glob(["vendor/sqlite-recover/**"]), compile_data = glob(["goals_migrations/**", "logs_migrations/**", "migrations/**"]), ) diff --git a/codex-rs/state/Cargo.toml b/codex-rs/state/Cargo.toml index a3b43f81d7..1f37c72bc8 100644 --- a/codex-rs/state/Cargo.toml +++ b/codex-rs/state/Cargo.toml @@ -3,6 +3,7 @@ name = "codex-state" version.workspace = true edition.workspace = true license.workspace = true +build = "build.rs" [dependencies] anyhow = { workspace = true } @@ -10,6 +11,7 @@ chrono = { workspace = true } clap = { workspace = true, features = ["derive", "env"] } codex-protocol = { workspace = true } dirs = { workspace = true } +libsqlite3-sys = { workspace = true } log = { workspace = true } owo-colors = { workspace = true } serde = { workspace = true, features = ["derive"] } @@ -25,5 +27,8 @@ uuid = { workspace = true } codex-git-utils = { workspace = true } pretty_assertions = { workspace = true } +[build-dependencies] +cc = { workspace = true } + [lints] workspace = true diff --git a/codex-rs/state/build.rs b/codex-rs/state/build.rs new file mode 100644 index 0000000000..5a38105019 --- /dev/null +++ b/codex-rs/state/build.rs @@ -0,0 +1,13 @@ +fn main() { + println!("cargo:rerun-if-changed=vendor/sqlite-recover/dbdata.c"); + println!("cargo:rerun-if-changed=vendor/sqlite-recover/sqlite3.h"); + println!("cargo:rerun-if-changed=vendor/sqlite-recover/sqlite3recover.c"); + println!("cargo:rerun-if-changed=vendor/sqlite-recover/sqlite3recover.h"); + + cc::Build::new() + .file("vendor/sqlite-recover/dbdata.c") + .file("vendor/sqlite-recover/sqlite3recover.c") + .include("vendor/sqlite-recover") + .warnings(false) + .compile("codex_sqlite_recover"); +} diff --git a/codex-rs/state/src/runtime.rs b/codex-rs/state/src/runtime.rs index 8c9c6d0267..5c6cb88dbc 100644 --- a/codex-rs/state/src/runtime.rs +++ b/codex-rs/state/src/runtime.rs @@ -61,6 +61,7 @@ mod backfill; mod goals; mod logs; mod memories; +mod recovery; mod remote_control; #[cfg(test)] mod test_support; @@ -294,6 +295,37 @@ async fn open_sqlite( telemetry_override: Option<&dyn DbTelemetry>, ) -> anyhow::Result { let options = base_sqlite_options(path).auto_vacuum(SqliteAutoVacuum::Incremental); + let pool = match connect_sqlite(options.clone(), spec, telemetry_override).await { + Ok(pool) => pool, + Err(err) => { + if !recovery::is_malformed_sqlite_error(&err) { + return Err(err); + } + recovery::recover_database(path, spec, migrator, &err).await?; + connect_sqlite(options.clone(), spec, telemetry_override).await? + } + }; + + match migrate_sqlite(&pool, migrator, spec, telemetry_override).await { + Ok(()) => Ok(pool), + Err(err) => { + if !recovery::is_malformed_sqlite_error(&err) { + return Err(err); + } + pool.close().await; + recovery::recover_database(path, spec, migrator, &err).await?; + let pool = connect_sqlite(options, spec, telemetry_override).await?; + migrate_sqlite(&pool, migrator, spec, telemetry_override).await?; + Ok(pool) + } + } +} + +async fn connect_sqlite( + options: SqliteConnectOptions, + spec: RuntimeDbSpec, + telemetry_override: Option<&dyn DbTelemetry>, +) -> anyhow::Result { let started = Instant::now(); let pool_result = SqlitePoolOptions::new() .max_connections(5) @@ -307,9 +339,17 @@ async fn open_sqlite( started.elapsed(), &pool_result, ); - let pool = pool_result?; + pool_result +} + +async fn migrate_sqlite( + pool: &SqlitePool, + migrator: &Migrator, + spec: RuntimeDbSpec, + telemetry_override: Option<&dyn DbTelemetry>, +) -> anyhow::Result<()> { let started = Instant::now(); - let migrate_result = migrator.run(&pool).await.map_err(anyhow::Error::from); + let migrate_result = migrator.run(pool).await.map_err(anyhow::Error::from); crate::telemetry::record_init_result( telemetry_override, spec.kind, @@ -317,8 +357,7 @@ async fn open_sqlite( started.elapsed(), &migrate_result, ); - migrate_result?; - Ok(pool) + migrate_result } pub(super) async fn ensure_backfill_state_row_in_pool( diff --git a/codex-rs/state/src/runtime/recovery.rs b/codex-rs/state/src/runtime/recovery.rs new file mode 100644 index 0000000000..49f9bd5d52 --- /dev/null +++ b/codex-rs/state/src/runtime/recovery.rs @@ -0,0 +1,723 @@ +use super::RuntimeDbSpec; +use anyhow::Context; +use anyhow::Result; +use log::LevelFilter; +use sqlx::ConnectOptions; +use sqlx::Row; +use sqlx::SqlitePool; +use sqlx::migrate::Migrator; +use sqlx::sqlite::SqliteConnectOptions; +use sqlx::sqlite::SqlitePoolOptions; +use std::borrow::Cow; +use std::collections::BTreeSet; +use std::ffi::OsString; +use std::path::Path; +use std::path::PathBuf; +use std::time::Duration; +use std::time::SystemTime; +use std::time::UNIX_EPOCH; +use tracing::warn; + +mod recover_api; + +const SQLITE_CORRUPT: i32 = 11; +const SQLITE_NOTADB: i32 = 26; + +#[derive(Debug)] +struct RecoveryPaths { + recovered_path: PathBuf, + backup_paths: Vec, +} + +pub(super) fn is_malformed_sqlite_error(err: &anyhow::Error) -> bool { + // Prefer SQLite result codes, but keep a message fallback for migration + // wrappers that stringify the underlying database error. + for cause in err.chain() { + if let Some(sqlx_err) = cause.downcast_ref::() + && sqlx_error_is_malformed(sqlx_err) + { + return true; + } + } + + err.chain() + .map(ToString::to_string) + .any(|message| error_message_is_malformed(message.as_str())) +} + +pub(super) async fn recover_database( + path: &Path, + spec: RuntimeDbSpec, + migrator: &Migrator, + original_error: &anyhow::Error, +) -> Result<()> { + let recovery = prepare_recovery_paths(path).await.with_context(|| { + format!( + "failed to prepare automatic recovery for {} at {}", + spec.label, + path.display() + ) + })?; + warn!( + "{} at {} appears malformed ({original_error}); attempting automatic recovery after backing up to {}", + spec.label, + path.display(), + format_backup_paths(&recovery.backup_paths) + ); + print_status(recovery_started_status( + path, + spec, + recovery.backup_paths.as_slice(), + )); + + match run_recovery(path, recovery.recovered_path.as_path(), migrator).await { + Ok(()) => { + if let Err(err) = + replace_with_recovered_database(path, recovery.recovered_path.as_path()).await + { + print_status(recovery_failed_status( + path, + spec, + recovery.backup_paths.as_slice(), + )); + return Err(err).with_context(|| { + format!( + "automatic recovery rebuilt {} at {} but failed to replace the original database; backup files remain at {}", + spec.label, + path.display(), + format_backup_paths(&recovery.backup_paths) + ) + }); + } + warn!( + "automatically recovered {} at {} with the SQLite recovery API", + spec.label, + path.display() + ); + print_status(recovery_completed_status(path, spec)); + Ok(()) + } + Err(err) => { + let _ = tokio::fs::remove_file(recovery.recovered_path.as_path()).await; + print_status(recovery_failed_status( + path, + spec, + recovery.backup_paths.as_slice(), + )); + Err(err).with_context(|| { + format!( + "automatic recovery failed for {} at {}; backup files remain at {}", + spec.label, + path.display(), + format_backup_paths(&recovery.backup_paths) + ) + }) + } + } +} + +fn print_status(message: String) { + // Keep startup recovery status on stderr so stdout remains available for + // command output and app-server JSON-RPC transports. + eprintln!("{message}"); +} + +fn sqlx_error_is_malformed(err: &sqlx::Error) -> bool { + match err { + sqlx::Error::Database(database_error) => { + let code = database_error + .code() + .unwrap_or(Cow::Borrowed("none")) + .to_string(); + sqlite_code_is_malformed(code.as_str()) + || error_message_is_malformed(database_error.message()) + } + _ => error_message_is_malformed(err.to_string().as_str()), + } +} + +fn sqlite_code_is_malformed(code: &str) -> bool { + let primary_code = code.parse::().ok().map(|code| code & 0xff); + matches!(primary_code, Some(SQLITE_CORRUPT | SQLITE_NOTADB)) +} + +fn error_message_is_malformed(message: &str) -> bool { + let message = message.to_ascii_lowercase(); + message.contains("database disk image is malformed") + || message.contains("file is not a database") + || message.contains("database schema is malformed") + || message.contains("database is corrupt") + || (message.contains("database") && message.contains("malformed")) +} + +async fn prepare_recovery_paths(path: &Path) -> Result { + if !tokio::fs::try_exists(path).await? { + anyhow::bail!("database file does not exist"); + } + + let suffix = recovery_suffix(); + let backup_paths = backup_sqlite_files(path, suffix.as_str()).await?; + if backup_paths.is_empty() { + anyhow::bail!("no database files were available to back up"); + } + let recovered_path = unique_sibling_path(path, suffix.as_str(), "recovered").await?; + Ok(RecoveryPaths { + recovered_path, + backup_paths, + }) +} + +async fn backup_sqlite_files(path: &Path, suffix: &str) -> Result> { + let mut backups = Vec::new(); + for sqlite_path in sqlite_paths(path) { + if tokio::fs::try_exists(sqlite_path.as_path()).await? { + let backup_path = unique_sibling_path(sqlite_path.as_path(), suffix, "bak").await?; + tokio::fs::copy(sqlite_path.as_path(), backup_path.as_path()).await?; + backups.push(backup_path); + } + } + Ok(backups) +} + +async fn unique_sibling_path(path: &Path, suffix: &str, extension: &str) -> Result { + let file_name = path.file_name().ok_or_else(|| { + anyhow::anyhow!("cannot create a recovery file name for {}", path.display()) + })?; + let mut sequence = 0; + loop { + let mut candidate = file_name.to_os_string(); + candidate.push(format!(".{suffix}.{sequence}.{extension}")); + let candidate = path.with_file_name(candidate); + if !tokio::fs::try_exists(candidate.as_path()).await? { + return Ok(candidate); + } + sequence += 1; + } +} + +async fn run_recovery(path: &Path, recovered_path: &Path, migrator: &Migrator) -> Result<()> { + let path = path.to_path_buf(); + let recovered_path = recovered_path.to_path_buf(); + let recovered_path_for_task = recovered_path.clone(); + tokio::task::spawn_blocking(move || { + recover_api::recover(path.as_path(), recovered_path_for_task.as_path()) + }) + .await + .context("sqlite recovery task panicked")??; + + let pool = open_recovered_pool(recovered_path.as_path()).await?; + assert_recovered_schema(&pool).await?; + assert_integrity_ok(&pool).await?; + match migrator.run(&pool).await { + Ok(()) => { + assert_integrity_ok(&pool).await?; + pool.close().await; + } + Err(err) => { + pool.close().await; + // Recovery can restore user tables while losing SQLx's bookkeeping + // table. Normalize through a fresh migrated DB before giving up. + rebuild_recovered_database(recovered_path.as_path(), migrator) + .await + .with_context(|| { + format!("failed to normalize recovered database after migration failure: {err}") + })?; + } + } + Ok(()) +} + +async fn open_recovered_pool(path: &Path) -> Result { + let options = SqliteConnectOptions::new() + .filename(path) + .create_if_missing(false) + .busy_timeout(Duration::from_secs(5)) + .log_statements(LevelFilter::Off); + Ok(SqlitePoolOptions::new() + .max_connections(1) + .connect_with(options) + .await?) +} + +async fn open_migrated_pool(path: &Path, migrator: &Migrator) -> Result { + let options = SqliteConnectOptions::new() + .filename(path) + .create_if_missing(true) + .busy_timeout(Duration::from_secs(5)) + .log_statements(LevelFilter::Off); + let pool = SqlitePoolOptions::new() + .max_connections(1) + .connect_with(options) + .await?; + migrator + .run(&pool) + .await + .context("failed to migrate fresh database for recovered data")?; + Ok(pool) +} + +async fn rebuild_recovered_database(recovered_path: &Path, migrator: &Migrator) -> Result<()> { + let normalized_path = + unique_sibling_path(recovered_path, "codex-recovery-normalized", "sqlite").await?; + let pool = open_migrated_pool(normalized_path.as_path(), migrator).await?; + let rebuild_result = async { + copy_recovered_tables(&pool, recovered_path).await?; + assert_recovered_schema(&pool).await?; + assert_integrity_ok(&pool).await?; + Ok::<(), anyhow::Error>(()) + } + .await; + pool.close().await; + + if let Err(err) = rebuild_result { + let _ = tokio::fs::remove_file(normalized_path.as_path()).await; + return Err(err); + } + + tokio::fs::remove_file(recovered_path).await?; + tokio::fs::rename(normalized_path, recovered_path).await?; + Ok(()) +} + +async fn copy_recovered_tables(pool: &SqlitePool, recovered_path: &Path) -> Result<()> { + let recovered_path = recovered_path.to_str().with_context(|| { + format!( + "recovered path is not valid UTF-8: {}", + recovered_path.display() + ) + })?; + sqlx::query("ATTACH DATABASE ? AS recovered") + .bind(recovered_path) + .execute(pool) + .await?; + sqlx::query("PRAGMA foreign_keys = OFF") + .execute(pool) + .await?; + + let copy_result = async { + let destination_tables = user_tables(pool, "main").await?; + let source_tables = user_tables(pool, "recovered").await?; + let mut copied_table_count = 0; + for table in source_tables { + if destination_tables.contains(&table) { + // Copy only columns that survived recovery and still exist in + // the current schema. Missing new columns rely on migration + // defaults. + if copy_current_schema_table(pool, table.as_str()).await? { + copied_table_count += 1; + } + } else { + copy_extra_recovered_table(pool, table.as_str()).await?; + copied_table_count += 1; + } + } + if copied_table_count == 0 { + anyhow::bail!("recovered database did not contain any current schema tables"); + } + Ok::<(), anyhow::Error>(()) + } + .await; + + let detach_result = sqlx::query("DETACH DATABASE recovered").execute(pool).await; + copy_result?; + detach_result?; + Ok(()) +} + +async fn user_tables(pool: &SqlitePool, schema: &str) -> Result> { + let sql = format!( + r#" +SELECT name +FROM {}.sqlite_schema +WHERE type = 'table' + AND name NOT LIKE 'sqlite_%' + AND name != '_sqlx_migrations' +ORDER BY name + "#, + quote_identifier(schema) + ); + let rows = sqlx::query_scalar::<_, String>(sql.as_str()) + .fetch_all(pool) + .await?; + Ok(rows.into_iter().collect()) +} + +async fn copy_current_schema_table(pool: &SqlitePool, table: &str) -> Result { + let destination_columns = table_columns(pool, "main", table).await?; + let source_columns = table_columns(pool, "recovered", table).await?; + let source_columns = source_columns.into_iter().collect::>(); + let columns = destination_columns + .into_iter() + .filter(|column| source_columns.contains(column)) + .collect::>(); + if columns.is_empty() { + return Ok(false); + } + + let column_list = columns + .iter() + .map(|column| quote_identifier(column)) + .collect::>() + .join(", "); + let table_name = quote_identifier(table); + let sql = format!( + "INSERT OR REPLACE INTO main.{table_name} ({column_list}) SELECT {column_list} FROM recovered.{table_name}" + ); + sqlx::query(sql.as_str()).execute(pool).await?; + Ok(true) +} + +async fn copy_extra_recovered_table(pool: &SqlitePool, table: &str) -> Result<()> { + let table_name = quote_identifier(table); + let sql = format!("CREATE TABLE main.{table_name} AS SELECT * FROM recovered.{table_name}"); + sqlx::query(sql.as_str()).execute(pool).await?; + Ok(()) +} + +async fn table_columns(pool: &SqlitePool, schema: &str, table: &str) -> Result> { + let sql = format!( + "SELECT name FROM {}.pragma_table_xinfo(?) WHERE hidden = 0 ORDER BY cid", + quote_identifier(schema) + ); + Ok(sqlx::query_scalar::<_, String>(sql.as_str()) + .bind(table) + .fetch_all(pool) + .await?) +} + +fn quote_identifier(identifier: &str) -> String { + format!("\"{}\"", identifier.replace('"', "\"\"")) +} + +async fn assert_recovered_schema(pool: &SqlitePool) -> Result<()> { + // A non-SQLite file can produce a valid empty database through recovery; + // accepting that would silently turn a damaged database into data loss. + let row = sqlx::query( + r#" +SELECT COUNT(*) AS table_count +FROM sqlite_schema +WHERE type = 'table' + AND name NOT LIKE 'sqlite_%' + AND name != '_sqlx_migrations' + "#, + ) + .fetch_one(pool) + .await?; + let table_count: i64 = row.try_get("table_count")?; + if table_count == 0 { + anyhow::bail!("SQLite recovery did not recover any user tables"); + } + Ok(()) +} + +async fn assert_integrity_ok(pool: &SqlitePool) -> Result<()> { + let rows = sqlx::query_scalar::<_, String>("PRAGMA integrity_check") + .fetch_all(pool) + .await?; + if !rows.iter().all(|row| row == "ok") { + anyhow::bail!( + "recovered database failed integrity_check: {}", + rows.join("; ") + ); + } + Ok(()) +} + +async fn replace_with_recovered_database(path: &Path, recovered_path: &Path) -> Result<()> { + // Stale WAL files belong to the damaged database and must not be replayed + // against the recovered replacement. + for sidecar in sqlite_sidecar_paths(path) { + match tokio::fs::remove_file(sidecar.as_path()).await { + Ok(()) => {} + Err(err) if err.kind() == std::io::ErrorKind::NotFound => {} + Err(err) => return Err(err.into()), + } + } + + #[cfg(windows)] + match tokio::fs::remove_file(path).await { + Ok(()) => {} + Err(err) if err.kind() == std::io::ErrorKind::NotFound => {} + Err(err) => return Err(err.into()), + } + + tokio::fs::rename(recovered_path, path).await?; + Ok(()) +} + +fn sqlite_paths(path: &Path) -> Vec { + let mut paths = vec![path.to_path_buf()]; + paths.extend(sqlite_sidecar_paths(path)); + paths +} + +fn sqlite_sidecar_paths(path: &Path) -> Vec { + ["-wal", "-shm"] + .into_iter() + .map(|suffix| { + let mut sidecar = OsString::from(path.as_os_str()); + sidecar.push(suffix); + PathBuf::from(sidecar) + }) + .collect() +} + +fn recovery_suffix() -> String { + let timestamp = SystemTime::now() + .duration_since(UNIX_EPOCH) + .map_or(0, |duration| duration.as_secs()); + format!("codex-recovery-{timestamp}") +} + +fn format_backup_paths(paths: &[PathBuf]) -> String { + paths + .iter() + .map(|path| path.display().to_string()) + .collect::>() + .join(", ") +} + +fn recovery_started_status(path: &Path, spec: RuntimeDbSpec, backup_paths: &[PathBuf]) -> String { + format!( + "Codex detected a malformed {} at {}. Please wait while Codex attempts to recover it automatically. Backup files: {}", + spec.label, + path.display(), + format_backup_paths(backup_paths) + ) +} + +fn recovery_completed_status(path: &Path, spec: RuntimeDbSpec) -> String { + format!( + "Codex successfully recovered {} at {}.", + spec.label, + path.display() + ) +} + +fn recovery_failed_status(path: &Path, spec: RuntimeDbSpec, backup_paths: &[PathBuf]) -> String { + format!( + "Codex could not automatically recover {} at {}. Backup files remain at {}.", + spec.label, + path.display(), + format_backup_paths(backup_paths) + ) +} + +#[cfg(test)] +mod tests { + use super::*; + use pretty_assertions::assert_eq; + use sqlx::migrate::Migrator; + use std::fs::OpenOptions; + use std::io::Seek; + use std::io::SeekFrom; + use std::io::Write; + + #[test] + fn detects_malformed_sqlite_messages() { + let err = anyhow::anyhow!("database disk image is malformed"); + + assert!(is_malformed_sqlite_error(&err)); + } + + #[test] + fn recovery_status_messages_include_path_and_backup() { + let db_path = Path::new("state.sqlite"); + let backup_path = PathBuf::from("state.sqlite.codex-recovery-1.0.bak"); + + assert_eq!( + recovery_started_status( + db_path, + super::super::STATE_DB, + std::slice::from_ref(&backup_path) + ), + "Codex detected a malformed state DB at state.sqlite. Please wait while Codex attempts to recover it automatically. Backup files: state.sqlite.codex-recovery-1.0.bak" + ); + assert_eq!( + recovery_completed_status(db_path, super::super::STATE_DB), + "Codex successfully recovered state DB at state.sqlite." + ); + assert_eq!( + recovery_failed_status(db_path, super::super::STATE_DB, &[backup_path]), + "Codex could not automatically recover state DB at state.sqlite. Backup files remain at state.sqlite.codex-recovery-1.0.bak." + ); + } + + #[tokio::test] + async fn recovery_preserves_backup_and_replaces_malformed_database() -> Result<()> { + let temp_dir = super::super::test_support::unique_temp_dir(); + tokio::fs::create_dir_all(temp_dir.as_path()).await?; + let db_path = temp_dir.join("sample.sqlite"); + create_sample_db(db_path.as_path()).await?; + corrupt_first_table_page(db_path.as_path())?; + + let err = anyhow::anyhow!("database disk image is malformed"); + recover_database( + db_path.as_path(), + super::super::STATE_DB, + &Migrator::DEFAULT, + &err, + ) + .await?; + + let rows = super::super::sqlite_integrity_check(db_path.as_path()).await?; + assert_eq!(rows, vec!["ok".to_string()]); + let backup_count = std::fs::read_dir(temp_dir.as_path())? + .filter_map(std::result::Result::ok) + .filter(|entry| { + entry + .file_name() + .to_string_lossy() + .contains(".codex-recovery-") + }) + .filter(|entry| entry.file_name().to_string_lossy().ends_with(".bak")) + .count(); + assert_eq!(backup_count, 1); + let _ = tokio::fs::remove_dir_all(temp_dir.as_path()).await; + Ok(()) + } + + #[tokio::test] + async fn recovery_normalizes_database_when_migration_metadata_is_lost() -> Result<()> { + let temp_dir = super::super::test_support::unique_temp_dir(); + tokio::fs::create_dir_all(temp_dir.as_path()).await?; + let db_path = temp_dir.join(super::super::STATE_DB.filename); + let migrator = crate::migrations::runtime_state_migrator(); + let pool = open_migrated_pool(db_path.as_path(), &migrator).await?; + let thread_id = "00000000-0000-0000-0000-000000000456"; + sqlx::query( + r#" +INSERT INTO threads ( + id, + rollout_path, + created_at, + updated_at, + source, + model_provider, + cwd, + title, + sandbox_policy, + approval_mode +) VALUES (?, ?, 1, 1, 'cli', 'test-provider', ?, 'survived recovery', 'read-only', 'on-request') + "#, + ) + .bind(thread_id) + .bind(temp_dir.join("session.jsonl").display().to_string()) + .bind(temp_dir.as_path().display().to_string()) + .execute(&pool) + .await?; + sqlx::query( + "CREATE TABLE extra_recovered_data (id INTEGER PRIMARY KEY, value TEXT NOT NULL)", + ) + .execute(&pool) + .await?; + sqlx::query("INSERT INTO extra_recovered_data (value) VALUES ('preserved')") + .execute(&pool) + .await?; + let page_size: i64 = sqlx::query_scalar("PRAGMA page_size") + .fetch_one(&pool) + .await?; + let migration_root_page: i64 = sqlx::query_scalar( + "SELECT rootpage FROM sqlite_schema WHERE name = '_sqlx_migrations'", + ) + .fetch_one(&pool) + .await?; + pool.close().await; + + corrupt_page( + db_path.as_path(), + page_size.try_into()?, + migration_root_page.try_into()?, + )?; + + let err = anyhow::anyhow!("database disk image is malformed"); + recover_database(db_path.as_path(), super::super::STATE_DB, &migrator, &err).await?; + + let pool = open_recovered_pool(db_path.as_path()).await?; + let title: String = sqlx::query_scalar("SELECT title FROM threads WHERE id = ?") + .bind(thread_id) + .fetch_one(&pool) + .await?; + let migration_count: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM _sqlx_migrations") + .fetch_one(&pool) + .await?; + let extra_value: String = + sqlx::query_scalar("SELECT value FROM extra_recovered_data WHERE id = 1") + .fetch_one(&pool) + .await?; + pool.close().await; + + assert_eq!(title, "survived recovery"); + assert_eq!(migration_count, migrator.migrations.len() as i64); + assert_eq!(extra_value, "preserved"); + let _ = tokio::fs::remove_dir_all(temp_dir.as_path()).await; + Ok(()) + } + + #[tokio::test] + async fn recovery_rejects_output_without_user_tables() -> Result<()> { + let temp_dir = super::super::test_support::unique_temp_dir(); + tokio::fs::create_dir_all(temp_dir.as_path()).await?; + let db_path = temp_dir.join("not-a-db.sqlite"); + tokio::fs::write(db_path.as_path(), b"not sqlite").await?; + let err = anyhow::anyhow!("file is not a database"); + + let recover_err = recover_database( + db_path.as_path(), + super::super::STATE_DB, + &Migrator::DEFAULT, + &err, + ) + .await + .expect_err("recovery without schema should fail"); + + assert!( + recover_err + .to_string() + .contains("automatic recovery failed"), + "unexpected error: {recover_err}" + ); + assert!(tokio::fs::try_exists(db_path.as_path()).await?); + let _ = tokio::fs::remove_dir_all(temp_dir.as_path()).await; + Ok(()) + } + + async fn create_sample_db(path: &Path) -> Result<()> { + let options = SqliteConnectOptions::new() + .filename(path) + .create_if_missing(true) + .log_statements(LevelFilter::Off); + let pool = SqlitePoolOptions::new() + .max_connections(1) + .connect_with(options) + .await?; + sqlx::query("CREATE TABLE sample (id INTEGER PRIMARY KEY, value TEXT NOT NULL)") + .execute(&pool) + .await?; + sqlx::query("INSERT INTO sample (value) VALUES ('one'), ('two')") + .execute(&pool) + .await?; + pool.close().await; + Ok(()) + } + + fn corrupt_first_table_page(path: &Path) -> Result<()> { + let mut bytes = std::fs::read(path)?; + if bytes.len() <= 4096 { + anyhow::bail!("sample database was smaller than two pages"); + } + bytes[4096] = 0; + std::fs::write(path, bytes)?; + Ok(()) + } + + fn corrupt_page(path: &Path, page_size: u64, page_number: u64) -> Result<()> { + let offset = page_size + .checked_mul(page_number.saturating_sub(1)) + .context("corrupt page offset overflowed")?; + let mut file = OpenOptions::new().write(true).open(path)?; + file.seek(SeekFrom::Start(offset))?; + file.write_all(&[0; 16])?; + Ok(()) + } +} diff --git a/codex-rs/state/src/runtime/recovery/recover_api.rs b/codex-rs/state/src/runtime/recovery/recover_api.rs new file mode 100644 index 0000000000..779406ab6b --- /dev/null +++ b/codex-rs/state/src/runtime/recovery/recover_api.rs @@ -0,0 +1,173 @@ +use anyhow::Context; +use anyhow::Result; +use libsqlite3_sys as ffi; +use std::ffi::CStr; +use std::ffi::CString; +use std::ffi::c_char; +use std::ffi::c_int; +use std::ffi::c_void; +use std::path::Path; +use std::ptr; + +const SQLITE_RECOVER_LOST_AND_FOUND: c_int = 1; + +#[repr(C)] +struct SqliteRecover { + _private: [u8; 0], +} + +unsafe extern "C" { + fn sqlite3_recover_init( + db: *mut ffi::sqlite3, + z_db: *const c_char, + z_uri: *const c_char, + ) -> *mut SqliteRecover; + fn sqlite3_recover_config(recover: *mut SqliteRecover, op: c_int, arg: *mut c_void) -> c_int; + fn sqlite3_recover_run(recover: *mut SqliteRecover) -> c_int; + fn sqlite3_recover_errmsg(recover: *mut SqliteRecover) -> *const c_char; + fn sqlite3_recover_errcode(recover: *mut SqliteRecover) -> c_int; + fn sqlite3_recover_finish(recover: *mut SqliteRecover) -> c_int; +} + +pub(super) fn recover(path: &Path, recovered_path: &Path) -> Result<()> { + let db = SqliteHandle::open(path)?; + let recovered_path = path_to_cstring(recovered_path)?; + let mut recovery = RecoveryHandle::new(db.as_ptr(), recovered_path.as_c_str())?; + recovery.configure_lost_and_found()?; + recovery.run()?; + recovery.finish() +} + +struct SqliteHandle { + db: *mut ffi::sqlite3, +} + +impl SqliteHandle { + fn open(path: &Path) -> Result { + let path = path_to_cstring(path)?; + let mut db = ptr::null_mut(); + let flags = ffi::SQLITE_OPEN_READWRITE | ffi::SQLITE_OPEN_URI; + // The recovery API reads pages through sqlite_dbpage on this handle. + // It does not depend on SQLx because the database may be malformed. + let rc = unsafe { ffi::sqlite3_open_v2(path.as_ptr(), &mut db, flags, ptr::null()) }; + if rc != ffi::SQLITE_OK { + let message = sqlite_error_message(db); + if !db.is_null() { + let _ = unsafe { ffi::sqlite3_close(db) }; + } + anyhow::bail!("failed to open malformed database for recovery ({rc}): {message}"); + } + Ok(Self { db }) + } + + fn as_ptr(&self) -> *mut ffi::sqlite3 { + self.db + } +} + +impl Drop for SqliteHandle { + fn drop(&mut self) { + if !self.db.is_null() { + let _ = unsafe { ffi::sqlite3_close(self.db) }; + } + } +} + +struct RecoveryHandle { + recover: *mut SqliteRecover, +} + +impl RecoveryHandle { + fn new(db: *mut ffi::sqlite3, recovered_path: &CStr) -> Result { + let recover = + unsafe { sqlite3_recover_init(db, c"main".as_ptr(), recovered_path.as_ptr()) }; + if recover.is_null() { + anyhow::bail!("failed to initialize SQLite recovery: out of memory"); + } + Ok(Self { recover }) + } + + fn configure_lost_and_found(&mut self) -> Result<()> { + // Match sqlite3 shell recovery behavior by keeping orphaned rows in a + // table instead of discarding pages not reachable from recovered schema. + let table_name = c"lost_and_found"; + self.configure( + SQLITE_RECOVER_LOST_AND_FOUND, + table_name.as_ptr().cast_mut().cast(), + ) + } + + fn configure(&mut self, op: c_int, arg: *mut c_void) -> Result<()> { + let rc = unsafe { sqlite3_recover_config(self.recover, op, arg) }; + if rc != ffi::SQLITE_OK { + anyhow::bail!( + "failed to configure SQLite recovery ({rc}): {}", + self.error_message() + ); + } + Ok(()) + } + + fn run(&mut self) -> Result<()> { + let rc = unsafe { sqlite3_recover_run(self.recover) }; + if rc != ffi::SQLITE_OK { + anyhow::bail!("SQLite recovery failed ({rc}): {}", self.error_message()); + } + Ok(()) + } + + fn finish(mut self) -> Result<()> { + let rc = unsafe { sqlite3_recover_finish(self.recover) }; + self.recover = ptr::null_mut(); + if rc != ffi::SQLITE_OK { + anyhow::bail!("SQLite recovery cleanup failed ({rc})"); + } + Ok(()) + } + + fn error_message(&self) -> String { + let errcode = unsafe { sqlite3_recover_errcode(self.recover) }; + let message = unsafe { sqlite3_recover_errmsg(self.recover) }; + format!("{errcode}: {}", c_string_lossy(message)) + } +} + +impl Drop for RecoveryHandle { + fn drop(&mut self) { + if !self.recover.is_null() { + let _ = unsafe { sqlite3_recover_finish(self.recover) }; + } + } +} + +fn sqlite_error_message(db: *mut ffi::sqlite3) -> String { + if db.is_null() { + return "out of memory".to_string(); + } + c_string_lossy(unsafe { ffi::sqlite3_errmsg(db) }) +} + +fn c_string_lossy(message: *const c_char) -> String { + if message.is_null() { + return "unknown error".to_string(); + } + unsafe { CStr::from_ptr(message) } + .to_string_lossy() + .into_owned() +} + +#[cfg(unix)] +fn path_to_cstring(path: &Path) -> Result { + use std::os::unix::ffi::OsStrExt; + + CString::new(path.as_os_str().as_bytes()) + .with_context(|| format!("path contains a NUL byte: {}", path.display())) +} + +#[cfg(not(unix))] +fn path_to_cstring(path: &Path) -> Result { + let path_str = path + .to_str() + .with_context(|| format!("path is not valid UTF-8: {}", path.display()))?; + CString::new(path_str).with_context(|| format!("path contains a NUL byte: {}", path.display())) +} diff --git a/codex-rs/state/vendor/sqlite-recover/README.md b/codex-rs/state/vendor/sqlite-recover/README.md new file mode 100644 index 0000000000..6612c1a922 --- /dev/null +++ b/codex-rs/state/vendor/sqlite-recover/README.md @@ -0,0 +1,14 @@ +Vendored from upstream SQLite Fossil trunk: + +- `ext/recover/sqlite3recover.c` +- `ext/recover/sqlite3recover.h` +- `ext/recover/dbdata.c` + +`sqlite3.h` is copied from the `libsqlite3-sys` 0.30.1 bundled SQLite +source so Cargo and Bazel compile these extension files with matching public +SQLite declarations without adding a build-dependency that would compile +SQLite a second time. + +These files implement SQLite's recover extension without invoking the +`sqlite3` command-line shell. They are compiled into `codex-state` and link +against the same `libsqlite3-sys` library that SQLx uses. diff --git a/codex-rs/state/vendor/sqlite-recover/dbdata.c b/codex-rs/state/vendor/sqlite-recover/dbdata.c new file mode 100644 index 0000000000..fabdbeb9c6 --- /dev/null +++ b/codex-rs/state/vendor/sqlite-recover/dbdata.c @@ -0,0 +1,1023 @@ +/* +** 2019-04-17 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +****************************************************************************** +** +** This file contains an implementation of two eponymous virtual tables, +** "sqlite_dbdata" and "sqlite_dbptr". Both modules require that the +** "sqlite_dbpage" eponymous virtual table be available. +** +** SQLITE_DBDATA: +** sqlite_dbdata is used to extract data directly from a database b-tree +** page and its associated overflow pages, bypassing the b-tree layer. +** The table schema is equivalent to: +** +** CREATE TABLE sqlite_dbdata( +** pgno INTEGER, +** cell INTEGER, +** field INTEGER, +** value ANY, +** schema TEXT HIDDEN +** ); +** +** IMPORTANT: THE VIRTUAL TABLE SCHEMA ABOVE IS SUBJECT TO CHANGE. IN THE +** FUTURE NEW NON-HIDDEN COLUMNS MAY BE ADDED BETWEEN "value" AND +** "schema". +** +** Each page of the database is inspected. If it cannot be interpreted as +** a b-tree page, or if it is a b-tree page containing 0 entries, the +** sqlite_dbdata table contains no rows for that page. Otherwise, the +** table contains one row for each field in the record associated with +** each cell on the page. For intkey b-trees, the key value is stored in +** field -1. +** +** For example, for the database: +** +** CREATE TABLE t1(a, b); -- root page is page 2 +** INSERT INTO t1(rowid, a, b) VALUES(5, 'v', 'five'); +** INSERT INTO t1(rowid, a, b) VALUES(10, 'x', 'ten'); +** +** the sqlite_dbdata table contains, as well as from entries related to +** page 1, content equivalent to: +** +** INSERT INTO sqlite_dbdata(pgno, cell, field, value) VALUES +** (2, 0, -1, 5 ), +** (2, 0, 0, 'v' ), +** (2, 0, 1, 'five'), +** (2, 1, -1, 10 ), +** (2, 1, 0, 'x' ), +** (2, 1, 1, 'ten' ); +** +** If database corruption is encountered, this module does not report an +** error. Instead, it attempts to extract as much data as possible and +** ignores the corruption. +** +** SQLITE_DBPTR: +** The sqlite_dbptr table has the following schema: +** +** CREATE TABLE sqlite_dbptr( +** pgno INTEGER, +** child INTEGER, +** schema TEXT HIDDEN +** ); +** +** It contains one entry for each b-tree pointer between a parent and +** child page in the database. +*/ + +#if !defined(SQLITEINT_H) +#include "sqlite3.h" + +typedef unsigned char u8; +typedef unsigned int u32; + +#endif +#include +#include + +#ifndef SQLITE_OMIT_VIRTUALTABLE + +#define DBDATA_PADDING_BYTES 100 + +typedef struct DbdataTable DbdataTable; +typedef struct DbdataCursor DbdataCursor; +typedef struct DbdataBuffer DbdataBuffer; + +/* +** Buffer type. +*/ +struct DbdataBuffer { + u8 *aBuf; + sqlite3_int64 nBuf; +}; + +/* Cursor object */ +struct DbdataCursor { + sqlite3_vtab_cursor base; /* Base class. Must be first */ + sqlite3_stmt *pStmt; /* For fetching database pages */ + + int iPgno; /* Current page number */ + u8 *aPage; /* Buffer containing page */ + int nPage; /* Size of aPage[] in bytes */ + int nCell; /* Number of cells on aPage[] */ + int iCell; /* Current cell number */ + int bOnePage; /* True to stop after one page */ + int szDb; + sqlite3_int64 iRowid; + + /* Only for the sqlite_dbdata table */ + DbdataBuffer rec; + sqlite3_int64 nRec; /* Size of pRec[] in bytes */ + sqlite3_int64 nHdr; /* Size of header in bytes */ + int iField; /* Current field number */ + u8 *pHdrPtr; + u8 *pPtr; + u32 enc; /* Text encoding */ + + sqlite3_int64 iIntkey; /* Integer key value */ +}; + +/* Table object */ +struct DbdataTable { + sqlite3_vtab base; /* Base class. Must be first */ + sqlite3 *db; /* The database connection */ + sqlite3_stmt *pStmt; /* For fetching database pages */ + int bPtr; /* True for sqlite3_dbptr table */ +}; + +/* Column and schema definitions for sqlite_dbdata */ +#define DBDATA_COLUMN_PGNO 0 +#define DBDATA_COLUMN_CELL 1 +#define DBDATA_COLUMN_FIELD 2 +#define DBDATA_COLUMN_VALUE 3 +#define DBDATA_COLUMN_SCHEMA 4 +#define DBDATA_SCHEMA \ + "CREATE TABLE x(" \ + " pgno INTEGER," \ + " cell INTEGER," \ + " field INTEGER," \ + " value ANY," \ + " schema TEXT HIDDEN" \ + ")" + +/* Column and schema definitions for sqlite_dbptr */ +#define DBPTR_COLUMN_PGNO 0 +#define DBPTR_COLUMN_CHILD 1 +#define DBPTR_COLUMN_SCHEMA 2 +#define DBPTR_SCHEMA \ + "CREATE TABLE x(" \ + " pgno INTEGER," \ + " child INTEGER," \ + " schema TEXT HIDDEN" \ + ")" + +/* +** Ensure the buffer passed as the first argument is at least nMin bytes +** in size. If an error occurs while attempting to resize the buffer, +** SQLITE_NOMEM is returned. Otherwise, SQLITE_OK. +*/ +static int dbdataBufferSize(DbdataBuffer *pBuf, sqlite3_int64 nMin){ + if( nMin>pBuf->nBuf ){ + sqlite3_int64 nNew = nMin+16384; + u8 *aNew = (u8*)sqlite3_realloc64(pBuf->aBuf, nNew); + + if( aNew==0 ) return SQLITE_NOMEM; + pBuf->aBuf = aNew; + pBuf->nBuf = nNew; + } + return SQLITE_OK; +} + +/* +** Release the allocation managed by buffer pBuf. +*/ +static void dbdataBufferFree(DbdataBuffer *pBuf){ + sqlite3_free(pBuf->aBuf); + memset(pBuf, 0, sizeof(*pBuf)); +} + +/* +** Connect to an sqlite_dbdata (pAux==0) or sqlite_dbptr (pAux!=0) virtual +** table. +*/ +static int dbdataConnect( + sqlite3 *db, + void *pAux, + int argc, const char *const*argv, + sqlite3_vtab **ppVtab, + char **pzErr +){ + DbdataTable *pTab = 0; + int rc = sqlite3_declare_vtab(db, pAux ? DBPTR_SCHEMA : DBDATA_SCHEMA); + + (void)argc; + (void)argv; + (void)pzErr; + sqlite3_vtab_config(db, SQLITE_VTAB_USES_ALL_SCHEMAS); + if( rc==SQLITE_OK ){ + pTab = (DbdataTable*)sqlite3_malloc64(sizeof(DbdataTable)); + if( pTab==0 ){ + rc = SQLITE_NOMEM; + }else{ + memset(pTab, 0, sizeof(DbdataTable)); + pTab->db = db; + pTab->bPtr = (pAux!=0); + } + } + + *ppVtab = (sqlite3_vtab*)pTab; + return rc; +} + +/* +** Disconnect from or destroy a sqlite_dbdata or sqlite_dbptr virtual table. +*/ +static int dbdataDisconnect(sqlite3_vtab *pVtab){ + DbdataTable *pTab = (DbdataTable*)pVtab; + if( pTab ){ + sqlite3_finalize(pTab->pStmt); + sqlite3_free(pVtab); + } + return SQLITE_OK; +} + +/* +** This function interprets two types of constraints: +** +** schema=? +** pgno=? +** +** If neither are present, idxNum is set to 0. If schema=? is present, +** the 0x01 bit in idxNum is set. If pgno=? is present, the 0x02 bit +** in idxNum is set. +** +** If both parameters are present, schema is in position 0 and pgno in +** position 1. +*/ +static int dbdataBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdx){ + DbdataTable *pTab = (DbdataTable*)tab; + int i; + int iSchema = -1; + int iPgno = -1; + int colSchema = (pTab->bPtr ? DBPTR_COLUMN_SCHEMA : DBDATA_COLUMN_SCHEMA); + + for(i=0; inConstraint; i++){ + struct sqlite3_index_constraint *p = &pIdx->aConstraint[i]; + if( p->op==SQLITE_INDEX_CONSTRAINT_EQ ){ + if( p->iColumn==colSchema ){ + if( p->usable==0 ) return SQLITE_CONSTRAINT; + iSchema = i; + } + if( p->iColumn==DBDATA_COLUMN_PGNO && p->usable ){ + iPgno = i; + } + } + } + + if( iSchema>=0 ){ + pIdx->aConstraintUsage[iSchema].argvIndex = 1; + pIdx->aConstraintUsage[iSchema].omit = 1; + } + if( iPgno>=0 ){ + pIdx->aConstraintUsage[iPgno].argvIndex = 1 + (iSchema>=0); + pIdx->aConstraintUsage[iPgno].omit = 1; + pIdx->estimatedCost = 100; + pIdx->estimatedRows = 50; + + if( pTab->bPtr==0 && pIdx->nOrderBy && pIdx->aOrderBy[0].desc==0 ){ + int iCol = pIdx->aOrderBy[0].iColumn; + if( pIdx->nOrderBy==1 ){ + pIdx->orderByConsumed = (iCol==0 || iCol==1); + }else if( pIdx->nOrderBy==2 && pIdx->aOrderBy[1].desc==0 && iCol==0 ){ + pIdx->orderByConsumed = (pIdx->aOrderBy[1].iColumn==1); + } + } + + }else{ + pIdx->estimatedCost = 100000000; + pIdx->estimatedRows = 1000000000; + } + pIdx->idxNum = (iSchema>=0 ? 0x01 : 0x00) | (iPgno>=0 ? 0x02 : 0x00); + return SQLITE_OK; +} + +/* +** Open a new sqlite_dbdata or sqlite_dbptr cursor. +*/ +static int dbdataOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){ + DbdataCursor *pCsr; + + pCsr = (DbdataCursor*)sqlite3_malloc64(sizeof(DbdataCursor)); + if( pCsr==0 ){ + return SQLITE_NOMEM; + }else{ + memset(pCsr, 0, sizeof(DbdataCursor)); + pCsr->base.pVtab = pVTab; + } + + *ppCursor = (sqlite3_vtab_cursor *)pCsr; + return SQLITE_OK; +} + +/* +** Restore a cursor object to the state it was in when first allocated +** by dbdataOpen(). +*/ +static void dbdataResetCursor(DbdataCursor *pCsr){ + DbdataTable *pTab = (DbdataTable*)(pCsr->base.pVtab); + if( pTab->pStmt==0 ){ + pTab->pStmt = pCsr->pStmt; + }else{ + sqlite3_finalize(pCsr->pStmt); + } + pCsr->pStmt = 0; + pCsr->iPgno = 1; + pCsr->iCell = 0; + pCsr->iField = 0; + pCsr->bOnePage = 0; + sqlite3_free(pCsr->aPage); + dbdataBufferFree(&pCsr->rec); + pCsr->aPage = 0; + pCsr->nRec = 0; +} + +/* +** Close an sqlite_dbdata or sqlite_dbptr cursor. +*/ +static int dbdataClose(sqlite3_vtab_cursor *pCursor){ + DbdataCursor *pCsr = (DbdataCursor*)pCursor; + dbdataResetCursor(pCsr); + sqlite3_free(pCsr); + return SQLITE_OK; +} + +/* +** Utility methods to decode 16 and 32-bit big-endian unsigned integers. +*/ +static u32 get_uint16(unsigned char *a){ + return (a[0]<<8)|a[1]; +} +static u32 get_uint32(unsigned char *a){ + return ((u32)a[0]<<24) + | ((u32)a[1]<<16) + | ((u32)a[2]<<8) + | ((u32)a[3]); +} + +/* +** Load page pgno from the database via the sqlite_dbpage virtual table. +** If successful, set (*ppPage) to point to a buffer containing the page +** data, (*pnPage) to the size of that buffer in bytes and return +** SQLITE_OK. In this case it is the responsibility of the caller to +** eventually free the buffer using sqlite3_free(). +** +** Or, if an error occurs, set both (*ppPage) and (*pnPage) to 0 and +** return an SQLite error code. +*/ +static int dbdataLoadPage( + DbdataCursor *pCsr, /* Cursor object */ + u32 pgno, /* Page number of page to load */ + u8 **ppPage, /* OUT: pointer to page buffer */ + int *pnPage /* OUT: Size of (*ppPage) in bytes */ +){ + int rc2; + int rc = SQLITE_OK; + sqlite3_stmt *pStmt = pCsr->pStmt; + + *ppPage = 0; + *pnPage = 0; + if( pgno>0 ){ + sqlite3_bind_int64(pStmt, 2, pgno); + if( SQLITE_ROW==sqlite3_step(pStmt) ){ + int nCopy = sqlite3_column_bytes(pStmt, 0); + if( nCopy>0 ){ + u8 *pPage; + pPage = (u8*)sqlite3_malloc64(nCopy + DBDATA_PADDING_BYTES); + if( pPage==0 ){ + rc = SQLITE_NOMEM; + }else{ + const u8 *pCopy = sqlite3_column_blob(pStmt, 0); + memcpy(pPage, pCopy, nCopy); + memset(&pPage[nCopy], 0, DBDATA_PADDING_BYTES); + } + *ppPage = pPage; + *pnPage = nCopy; + } + } + rc2 = sqlite3_reset(pStmt); + if( rc==SQLITE_OK ) rc = rc2; + } + + return rc; +} + +/* +** Read a varint. Put the value in *pVal and return the number of bytes. +*/ +static int dbdataGetVarint(const u8 *z, sqlite3_int64 *pVal){ + sqlite3_uint64 u = 0; + int i; + for(i=0; i<8; i++){ + u = (u<<7) + (z[i]&0x7f); + if( (z[i]&0x80)==0 ){ *pVal = (sqlite3_int64)u; return i+1; } + } + u = (u<<8) + (z[i]&0xff); + *pVal = (sqlite3_int64)u; + return 9; +} + +/* +** Like dbdataGetVarint(), but set the output to 0 if it is less than 0 +** or greater than 0xFFFFFFFF. This can be used for all varints in an +** SQLite database except for key values in intkey tables. +*/ +static int dbdataGetVarintU32(const u8 *z, sqlite3_int64 *pVal){ + sqlite3_int64 val; + int nRet = dbdataGetVarint(z, &val); + if( val<0 || val>0xFFFFFFFF ) val = 0; + *pVal = val; + return nRet; +} + +/* +** Return the number of bytes of space used by an SQLite value of type +** eType. +*/ +static int dbdataValueBytes(int eType){ + switch( eType ){ + case 0: case 8: case 9: + case 10: case 11: + return 0; + case 1: + return 1; + case 2: + return 2; + case 3: + return 3; + case 4: + return 4; + case 5: + return 6; + case 6: + case 7: + return 8; + default: + if( eType>0 ){ + return ((eType-12) / 2); + } + return 0; + } +} + +/* +** Load a value of type eType from buffer pData and use it to set the +** result of context object pCtx. +*/ +static void dbdataValue( + sqlite3_context *pCtx, + u32 enc, + int eType, + u8 *pData, + sqlite3_int64 nData +){ + if( eType>=0 ){ + if( dbdataValueBytes(eType)<=nData ){ + switch( eType ){ + case 0: + case 10: + case 11: + sqlite3_result_null(pCtx); + break; + + case 8: + sqlite3_result_int(pCtx, 0); + break; + case 9: + sqlite3_result_int(pCtx, 1); + break; + + case 1: case 2: case 3: case 4: case 5: case 6: case 7: { + sqlite3_uint64 v = (signed char)pData[0]; + pData++; + switch( eType ){ + case 7: + case 6: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2; + case 5: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2; + case 4: v = (v<<8) + pData[0]; pData++; + case 3: v = (v<<8) + pData[0]; pData++; + case 2: v = (v<<8) + pData[0]; pData++; + } + + if( eType==7 ){ + double r; + memcpy(&r, &v, sizeof(r)); + sqlite3_result_double(pCtx, r); + }else{ + sqlite3_result_int64(pCtx, (sqlite3_int64)v); + } + break; + } + + default: { + int n = ((eType-12) / 2); + if( eType % 2 ){ + switch( enc ){ + #ifndef SQLITE_OMIT_UTF16 + case SQLITE_UTF16BE: + sqlite3_result_text16be(pCtx, (void*)pData, n, SQLITE_TRANSIENT); + break; + case SQLITE_UTF16LE: + sqlite3_result_text16le(pCtx, (void*)pData, n, SQLITE_TRANSIENT); + break; + #endif + default: + sqlite3_result_text(pCtx, (char*)pData, n, SQLITE_TRANSIENT); + break; + } + }else{ + sqlite3_result_blob(pCtx, pData, n, SQLITE_TRANSIENT); + } + } + } + }else{ + if( eType==7 ){ + sqlite3_result_double(pCtx, 0.0); + }else if( eType<7 ){ + sqlite3_result_int(pCtx, 0); + }else if( eType%2 ){ + sqlite3_result_text(pCtx, "", 0, SQLITE_STATIC); + }else{ + sqlite3_result_blob(pCtx, "", 0, SQLITE_STATIC); + } + } + } +} + +/* This macro is a copy of the MX_CELL() macro in the SQLite core. Given +** a page-size, it returns the maximum number of cells that may be present +** on the page. */ +#define DBDATA_MX_CELL(pgsz) ((pgsz-8)/6) + +/* Maximum number of fields that may appear in a single record. This is +** the "hard-limit", according to comments in sqliteLimit.h. */ +#define DBDATA_MX_FIELD 32676 + +/* +** Move an sqlite_dbdata or sqlite_dbptr cursor to the next entry. +*/ +static int dbdataNext(sqlite3_vtab_cursor *pCursor){ + DbdataCursor *pCsr = (DbdataCursor*)pCursor; + DbdataTable *pTab = (DbdataTable*)pCursor->pVtab; + + pCsr->iRowid++; + while( 1 ){ + int rc; + int iOff = (pCsr->iPgno==1 ? 100 : 0); + int bNextPage = 0; + + if( pCsr->aPage==0 ){ + while( 1 ){ + if( pCsr->bOnePage==0 && pCsr->iPgno>pCsr->szDb ) return SQLITE_OK; + rc = dbdataLoadPage(pCsr, pCsr->iPgno, &pCsr->aPage, &pCsr->nPage); + if( rc!=SQLITE_OK ) return rc; + if( pCsr->aPage && pCsr->nPage>=256 ) break; + sqlite3_free(pCsr->aPage); + pCsr->aPage = 0; + if( pCsr->bOnePage ) return SQLITE_OK; + pCsr->iPgno++; + } + + assert( iOff+3+2<=pCsr->nPage ); + pCsr->iCell = pTab->bPtr ? -2 : 0; + pCsr->nCell = get_uint16(&pCsr->aPage[iOff+3]); + if( pCsr->nCell>DBDATA_MX_CELL(pCsr->nPage) ){ + pCsr->nCell = DBDATA_MX_CELL(pCsr->nPage); + } + } + + if( pTab->bPtr ){ + if( pCsr->aPage[iOff]!=0x02 && pCsr->aPage[iOff]!=0x05 ){ + pCsr->iCell = pCsr->nCell; + } + pCsr->iCell++; + if( pCsr->iCell>=pCsr->nCell ){ + sqlite3_free(pCsr->aPage); + pCsr->aPage = 0; + if( pCsr->bOnePage ) return SQLITE_OK; + pCsr->iPgno++; + }else{ + return SQLITE_OK; + } + }else{ + /* If there is no record loaded, load it now. */ + assert( pCsr->rec.aBuf!=0 || pCsr->nRec==0 ); + if( pCsr->nRec==0 ){ + int bHasRowid = 0; + int nPointer = 0; + sqlite3_int64 nPayload = 0; + sqlite3_int64 nHdr = 0; + int iHdr; + int U, X; + int nLocal; + + switch( pCsr->aPage[iOff] ){ + case 0x02: + nPointer = 4; + break; + case 0x0a: + break; + case 0x0d: + bHasRowid = 1; + break; + default: + /* This is not a b-tree page with records on it. Continue. */ + pCsr->iCell = pCsr->nCell; + break; + } + + if( pCsr->iCell>=pCsr->nCell ){ + bNextPage = 1; + }else{ + int iCellPtr = iOff + 8 + nPointer + pCsr->iCell*2; + + if( iCellPtr>pCsr->nPage ){ + bNextPage = 1; + }else{ + iOff = get_uint16(&pCsr->aPage[iCellPtr]); + } + + /* For an interior node cell, skip past the child-page number */ + iOff += nPointer; + + /* Load the "byte of payload including overflow" field */ + if( bNextPage || iOff>pCsr->nPage || iOff<=iCellPtr ){ + bNextPage = 1; + }else{ + iOff += dbdataGetVarintU32(&pCsr->aPage[iOff], &nPayload); + if( nPayload>0x7fffff00 ) nPayload &= 0x3fff; + if( nPayload==0 ) nPayload = 1; + } + + /* If this is a leaf intkey cell, load the rowid */ + if( bHasRowid && !bNextPage && iOffnPage ){ + iOff += dbdataGetVarint(&pCsr->aPage[iOff], &pCsr->iIntkey); + } + + /* Figure out how much data to read from the local page */ + U = pCsr->nPage; + if( bHasRowid ){ + X = U-35; + }else{ + X = ((U-12)*64/255)-23; + } + if( nPayload<=X ){ + nLocal = nPayload; + }else{ + int M, K; + M = ((U-12)*32/255)-23; + K = M+((nPayload-M)%(U-4)); + if( K<=X ){ + nLocal = K; + }else{ + nLocal = M; + } + } + + if( bNextPage || nLocal+iOff>pCsr->nPage ){ + bNextPage = 1; + }else{ + + /* Allocate space for payload. And a bit more to catch small buffer + ** overruns caused by attempting to read a varint or similar from + ** near the end of a corrupt record. */ + rc = dbdataBufferSize(&pCsr->rec, nPayload+DBDATA_PADDING_BYTES); + if( rc!=SQLITE_OK ) return rc; + assert( pCsr->rec.aBuf!=0 ); + assert( nPayload!=0 ); + + /* Load the nLocal bytes of payload */ + memcpy(pCsr->rec.aBuf, &pCsr->aPage[iOff], nLocal); + iOff += nLocal; + + /* Load content from overflow pages */ + if( nPayload>nLocal ){ + sqlite3_int64 nRem = nPayload - nLocal; + u32 pgnoOvfl = get_uint32(&pCsr->aPage[iOff]); + while( nRem>0 ){ + u8 *aOvfl = 0; + int nOvfl = 0; + int nCopy; + rc = dbdataLoadPage(pCsr, pgnoOvfl, &aOvfl, &nOvfl); + assert( rc!=SQLITE_OK || aOvfl==0 || nOvfl==pCsr->nPage ); + if( rc!=SQLITE_OK ) return rc; + if( aOvfl==0 ) break; + + nCopy = U-4; + if( nCopy>nRem ) nCopy = nRem; + memcpy(&pCsr->rec.aBuf[nPayload-nRem], &aOvfl[4], nCopy); + nRem -= nCopy; + + pgnoOvfl = get_uint32(aOvfl); + sqlite3_free(aOvfl); + } + nPayload -= nRem; + } + memset(&pCsr->rec.aBuf[nPayload], 0, DBDATA_PADDING_BYTES); + pCsr->nRec = nPayload; + + iHdr = dbdataGetVarintU32(pCsr->rec.aBuf, &nHdr); + if( nHdr>nPayload ) nHdr = 0; + pCsr->nHdr = nHdr; + pCsr->pHdrPtr = &pCsr->rec.aBuf[iHdr]; + pCsr->pPtr = &pCsr->rec.aBuf[pCsr->nHdr]; + pCsr->iField = (bHasRowid ? -1 : 0); + } + } + }else{ + pCsr->iField++; + if( pCsr->iField>0 ){ + sqlite3_int64 iType; + if( pCsr->pHdrPtr>=&pCsr->rec.aBuf[pCsr->nRec] + || pCsr->iField>=DBDATA_MX_FIELD + ){ + bNextPage = 1; + }else{ + int szField = 0; + pCsr->pHdrPtr += dbdataGetVarintU32(pCsr->pHdrPtr, &iType); + szField = dbdataValueBytes(iType); + if( (pCsr->nRec - (pCsr->pPtr - pCsr->rec.aBuf))pPtr = &pCsr->rec.aBuf[pCsr->nRec]; + }else{ + pCsr->pPtr += szField; + } + } + } + } + + if( bNextPage ){ + sqlite3_free(pCsr->aPage); + pCsr->aPage = 0; + pCsr->nRec = 0; + if( pCsr->bOnePage ) return SQLITE_OK; + pCsr->iPgno++; + }else{ + if( pCsr->iField<0 || pCsr->pHdrPtr<&pCsr->rec.aBuf[pCsr->nHdr] ){ + return SQLITE_OK; + } + + /* Advance to the next cell. The next iteration of the loop will load + ** the record and so on. */ + pCsr->nRec = 0; + pCsr->iCell++; + } + } + } + + assert( !"can't get here" ); + return SQLITE_OK; +} + +/* +** Return true if the cursor is at EOF. +*/ +static int dbdataEof(sqlite3_vtab_cursor *pCursor){ + DbdataCursor *pCsr = (DbdataCursor*)pCursor; + return pCsr->aPage==0; +} + +/* +** Return true if nul-terminated string zSchema ends in "()". Or false +** otherwise. +*/ +static int dbdataIsFunction(const char *zSchema){ + size_t n = strlen(zSchema); + if( n>2 && zSchema[n-2]=='(' && zSchema[n-1]==')' ){ + return (int)n-2; + } + return 0; +} + +/* +** Determine the size in pages of database zSchema (where zSchema is +** "main", "temp" or the name of an attached database) and set +** pCsr->szDb accordingly. If successful, return SQLITE_OK. Otherwise, +** an SQLite error code. +*/ +static int dbdataDbsize(DbdataCursor *pCsr, const char *zSchema){ + DbdataTable *pTab = (DbdataTable*)pCsr->base.pVtab; + char *zSql = 0; + int rc, rc2; + int nFunc = 0; + sqlite3_stmt *pStmt = 0; + + if( (nFunc = dbdataIsFunction(zSchema))>0 ){ + zSql = sqlite3_mprintf("SELECT %.*s(0)", nFunc, zSchema); + }else{ + zSql = sqlite3_mprintf("PRAGMA %Q.page_count", zSchema); + } + if( zSql==0 ) return SQLITE_NOMEM; + + rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pStmt, 0); + sqlite3_free(zSql); + if( rc==SQLITE_OK && sqlite3_step(pStmt)==SQLITE_ROW ){ + pCsr->szDb = sqlite3_column_int(pStmt, 0); + } + rc2 = sqlite3_finalize(pStmt); + if( rc==SQLITE_OK ) rc = rc2; + return rc; +} + +/* +** Attempt to figure out the encoding of the database by retrieving page 1 +** and inspecting the header field. If successful, set the pCsr->enc variable +** and return SQLITE_OK. Otherwise, return an SQLite error code. +*/ +static int dbdataGetEncoding(DbdataCursor *pCsr){ + int rc = SQLITE_OK; + int nPg1 = 0; + u8 *aPg1 = 0; + rc = dbdataLoadPage(pCsr, 1, &aPg1, &nPg1); + if( rc==SQLITE_OK && nPg1>=(56+4) ){ + pCsr->enc = get_uint32(&aPg1[56]); + } + sqlite3_free(aPg1); + return rc; +} + + +/* +** xFilter method for sqlite_dbdata and sqlite_dbptr. +*/ +static int dbdataFilter( + sqlite3_vtab_cursor *pCursor, + int idxNum, const char *idxStr, + int argc, sqlite3_value **argv +){ + DbdataCursor *pCsr = (DbdataCursor*)pCursor; + DbdataTable *pTab = (DbdataTable*)pCursor->pVtab; + int rc = SQLITE_OK; + const char *zSchema = "main"; + (void)idxStr; + (void)argc; + + dbdataResetCursor(pCsr); + assert( pCsr->iPgno==1 ); + if( idxNum & 0x01 ){ + zSchema = (const char*)sqlite3_value_text(argv[0]); + if( zSchema==0 ) zSchema = ""; + } + if( idxNum & 0x02 ){ + pCsr->iPgno = sqlite3_value_int(argv[(idxNum & 0x01)]); + pCsr->bOnePage = 1; + }else{ + rc = dbdataDbsize(pCsr, zSchema); + } + + if( rc==SQLITE_OK ){ + int nFunc = 0; + if( pTab->pStmt ){ + pCsr->pStmt = pTab->pStmt; + pTab->pStmt = 0; + }else if( (nFunc = dbdataIsFunction(zSchema))>0 ){ + char *zSql = sqlite3_mprintf("SELECT %.*s(?2)", nFunc, zSchema); + if( zSql==0 ){ + rc = SQLITE_NOMEM; + }else{ + rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pStmt, 0); + sqlite3_free(zSql); + } + }else{ + rc = sqlite3_prepare_v2(pTab->db, + "SELECT data FROM sqlite_dbpage(?) WHERE pgno=?", -1, + &pCsr->pStmt, 0 + ); + } + } + if( rc==SQLITE_OK ){ + rc = sqlite3_bind_text(pCsr->pStmt, 1, zSchema, -1, SQLITE_TRANSIENT); + } + + /* Try to determine the encoding of the db by inspecting the header + ** field on page 1. */ + if( rc==SQLITE_OK ){ + rc = dbdataGetEncoding(pCsr); + } + + if( rc!=SQLITE_OK ){ + pTab->base.zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(pTab->db)); + } + + if( rc==SQLITE_OK ){ + rc = dbdataNext(pCursor); + } + return rc; +} + +/* +** Return a column for the sqlite_dbdata or sqlite_dbptr table. +*/ +static int dbdataColumn( + sqlite3_vtab_cursor *pCursor, + sqlite3_context *ctx, + int i +){ + DbdataCursor *pCsr = (DbdataCursor*)pCursor; + DbdataTable *pTab = (DbdataTable*)pCursor->pVtab; + if( pTab->bPtr ){ + switch( i ){ + case DBPTR_COLUMN_PGNO: + sqlite3_result_int64(ctx, pCsr->iPgno); + break; + case DBPTR_COLUMN_CHILD: { + int iOff = pCsr->iPgno==1 ? 100 : 0; + if( pCsr->iCell<0 ){ + iOff += 8; + }else{ + iOff += 12 + pCsr->iCell*2; + if( iOff>pCsr->nPage ) return SQLITE_OK; + iOff = get_uint16(&pCsr->aPage[iOff]); + } + if( iOff<=pCsr->nPage ){ + sqlite3_result_int64(ctx, get_uint32(&pCsr->aPage[iOff])); + } + break; + } + } + }else{ + switch( i ){ + case DBDATA_COLUMN_PGNO: + sqlite3_result_int64(ctx, pCsr->iPgno); + break; + case DBDATA_COLUMN_CELL: + sqlite3_result_int(ctx, pCsr->iCell); + break; + case DBDATA_COLUMN_FIELD: + sqlite3_result_int(ctx, pCsr->iField); + break; + case DBDATA_COLUMN_VALUE: { + if( pCsr->iField<0 ){ + sqlite3_result_int64(ctx, pCsr->iIntkey); + }else if( &pCsr->rec.aBuf[pCsr->nRec] >= pCsr->pPtr ){ + sqlite3_int64 iType; + dbdataGetVarintU32(pCsr->pHdrPtr, &iType); + dbdataValue( + ctx, pCsr->enc, iType, pCsr->pPtr, + &pCsr->rec.aBuf[pCsr->nRec] - pCsr->pPtr + ); + } + break; + } + } + } + return SQLITE_OK; +} + +/* +** Return the rowid for an sqlite_dbdata or sqlite_dptr table. +*/ +static int dbdataRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){ + DbdataCursor *pCsr = (DbdataCursor*)pCursor; + *pRowid = pCsr->iRowid; + return SQLITE_OK; +} + + +/* +** Invoke this routine to register the "sqlite_dbdata" virtual table module +*/ +static int sqlite3DbdataRegister(sqlite3 *db){ + static sqlite3_module dbdata_module = { + 0, /* iVersion */ + 0, /* xCreate */ + dbdataConnect, /* xConnect */ + dbdataBestIndex, /* xBestIndex */ + dbdataDisconnect, /* xDisconnect */ + 0, /* xDestroy */ + dbdataOpen, /* xOpen - open a cursor */ + dbdataClose, /* xClose - close a cursor */ + dbdataFilter, /* xFilter - configure scan constraints */ + dbdataNext, /* xNext - advance a cursor */ + dbdataEof, /* xEof - check for end of scan */ + dbdataColumn, /* xColumn - read data */ + dbdataRowid, /* xRowid - read data */ + 0, /* xUpdate */ + 0, /* xBegin */ + 0, /* xSync */ + 0, /* xCommit */ + 0, /* xRollback */ + 0, /* xFindMethod */ + 0, /* xRename */ + 0, /* xSavepoint */ + 0, /* xRelease */ + 0, /* xRollbackTo */ + 0, /* xShadowName */ + 0 /* xIntegrity */ + }; + + int rc = sqlite3_create_module(db, "sqlite_dbdata", &dbdata_module, 0); + if( rc==SQLITE_OK ){ + rc = sqlite3_create_module(db, "sqlite_dbptr", &dbdata_module, (void*)1); + } + return rc; +} + +#ifdef _WIN32 +__declspec(dllexport) +#endif +int sqlite3_dbdata_init( + sqlite3 *db, + char **pzErrMsg, + const sqlite3_api_routines *pApi +){ + (void)pzErrMsg; + return sqlite3DbdataRegister(db); +} + +#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */ diff --git a/codex-rs/state/vendor/sqlite-recover/sqlite3.h b/codex-rs/state/vendor/sqlite-recover/sqlite3.h new file mode 100644 index 0000000000..57df8dcf20 --- /dev/null +++ b/codex-rs/state/vendor/sqlite-recover/sqlite3.h @@ -0,0 +1,13425 @@ +/* +** 2001-09-15 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** This header file defines the interface that the SQLite library +** presents to client programs. If a C-function, structure, datatype, +** or constant definition does not appear in this file, then it is +** not a published API of SQLite, is subject to change without +** notice, and should not be referenced by programs that use SQLite. +** +** Some of the definitions that are in this file are marked as +** "experimental". Experimental interfaces are normally new +** features recently added to SQLite. We do not anticipate changes +** to experimental interfaces but reserve the right to make minor changes +** if experience from use "in the wild" suggest such changes are prudent. +** +** The official C-language API documentation for SQLite is derived +** from comments in this file. This file is the authoritative source +** on how SQLite interfaces are supposed to operate. +** +** The name of this file under configuration management is "sqlite.h.in". +** The makefile makes some minor changes to this file (such as inserting +** the version number) and changes its name to "sqlite3.h" as +** part of the build process. +*/ +#ifndef SQLITE3_H +#define SQLITE3_H +#include /* Needed for the definition of va_list */ + +/* +** Make sure we can call this stuff from C++. +*/ +#ifdef __cplusplus +extern "C" { +#endif + + +/* +** Facilitate override of interface linkage and calling conventions. +** Be aware that these macros may not be used within this particular +** translation of the amalgamation and its associated header file. +** +** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the +** compiler that the target identifier should have external linkage. +** +** The SQLITE_CDECL macro is used to set the calling convention for +** public functions that accept a variable number of arguments. +** +** The SQLITE_APICALL macro is used to set the calling convention for +** public functions that accept a fixed number of arguments. +** +** The SQLITE_STDCALL macro is no longer used and is now deprecated. +** +** The SQLITE_CALLBACK macro is used to set the calling convention for +** function pointers. +** +** The SQLITE_SYSAPI macro is used to set the calling convention for +** functions provided by the operating system. +** +** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and +** SQLITE_SYSAPI macros are used only when building for environments +** that require non-default calling conventions. +*/ +#ifndef SQLITE_EXTERN +# define SQLITE_EXTERN extern +#endif +#ifndef SQLITE_API +# define SQLITE_API +#endif +#ifndef SQLITE_CDECL +# define SQLITE_CDECL +#endif +#ifndef SQLITE_APICALL +# define SQLITE_APICALL +#endif +#ifndef SQLITE_STDCALL +# define SQLITE_STDCALL SQLITE_APICALL +#endif +#ifndef SQLITE_CALLBACK +# define SQLITE_CALLBACK +#endif +#ifndef SQLITE_SYSAPI +# define SQLITE_SYSAPI +#endif + +/* +** These no-op macros are used in front of interfaces to mark those +** interfaces as either deprecated or experimental. New applications +** should not use deprecated interfaces - they are supported for backwards +** compatibility only. Application writers should be aware that +** experimental interfaces are subject to change in point releases. +** +** These macros used to resolve to various kinds of compiler magic that +** would generate warning messages when they were used. But that +** compiler magic ended up generating such a flurry of bug reports +** that we have taken it all out and gone back to using simple +** noop macros. +*/ +#define SQLITE_DEPRECATED +#define SQLITE_EXPERIMENTAL + +/* +** Ensure these symbols were not defined by some previous header file. +*/ +#ifdef SQLITE_VERSION +# undef SQLITE_VERSION +#endif +#ifdef SQLITE_VERSION_NUMBER +# undef SQLITE_VERSION_NUMBER +#endif + +/* +** CAPI3REF: Compile-Time Library Version Numbers +** +** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header +** evaluates to a string literal that is the SQLite version in the +** format "X.Y.Z" where X is the major version number (always 3 for +** SQLite3) and Y is the minor version number and Z is the release number.)^ +** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer +** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same +** numbers used in [SQLITE_VERSION].)^ +** The SQLITE_VERSION_NUMBER for any given release of SQLite will also +** be larger than the release from which it is derived. Either Y will +** be held constant and Z will be incremented or else Y will be incremented +** and Z will be reset to zero. +** +** Since [version 3.6.18] ([dateof:3.6.18]), +** SQLite source code has been stored in the +** Fossil configuration management +** system. ^The SQLITE_SOURCE_ID macro evaluates to +** a string which identifies a particular check-in of SQLite +** within its configuration management system. ^The SQLITE_SOURCE_ID +** string contains the date and time of the check-in (UTC) and a SHA1 +** or SHA3-256 hash of the entire source tree. If the source code has +** been edited in any way since it was last checked in, then the last +** four hexadecimal digits of the hash may be modified. +** +** See also: [sqlite3_libversion()], +** [sqlite3_libversion_number()], [sqlite3_sourceid()], +** [sqlite_version()] and [sqlite_source_id()]. +*/ +#define SQLITE_VERSION "3.46.0" +#define SQLITE_VERSION_NUMBER 3046000 +#define SQLITE_SOURCE_ID "2024-05-23 13:25:27 96c92aba00c8375bc32fafcdf12429c58bd8aabfcadab6683e35bbb9cdebf19e" + +/* +** CAPI3REF: Run-Time Library Version Numbers +** KEYWORDS: sqlite3_version sqlite3_sourceid +** +** These interfaces provide the same information as the [SQLITE_VERSION], +** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros +** but are associated with the library instead of the header file. ^(Cautious +** programmers might include assert() statements in their application to +** verify that values returned by these interfaces match the macros in +** the header, and thus ensure that the application is +** compiled with matching library and header files. +** +** 
+** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
+** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
+** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
+**
)^ +** +** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] +** macro. ^The sqlite3_libversion() function returns a pointer to the +** to the sqlite3_version[] string constant. The sqlite3_libversion() +** function is provided for use in DLLs since DLL users usually do not have +** direct access to string constants within the DLL. ^The +** sqlite3_libversion_number() function returns an integer equal to +** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns +** a pointer to a string constant whose value is the same as the +** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built +** using an edited copy of [the amalgamation], then the last four characters +** of the hash might be different from [SQLITE_SOURCE_ID].)^ +** +** See also: [sqlite_version()] and [sqlite_source_id()]. +*/ +SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; +SQLITE_API const char *sqlite3_libversion(void); +SQLITE_API const char *sqlite3_sourceid(void); +SQLITE_API int sqlite3_libversion_number(void); + +/* +** CAPI3REF: Run-Time Library Compilation Options Diagnostics +** +** ^The sqlite3_compileoption_used() function returns 0 or 1 +** indicating whether the specified option was defined at +** compile time. ^The SQLITE_ prefix may be omitted from the +** option name passed to sqlite3_compileoption_used(). +** +** ^The sqlite3_compileoption_get() function allows iterating +** over the list of options that were defined at compile time by +** returning the N-th compile time option string. ^If N is out of range, +** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ +** prefix is omitted from any strings returned by +** sqlite3_compileoption_get(). +** +** ^Support for the diagnostic functions sqlite3_compileoption_used() +** and sqlite3_compileoption_get() may be omitted by specifying the +** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. +** +** See also: SQL functions [sqlite_compileoption_used()] and +** [sqlite_compileoption_get()] and the [compile_options pragma]. +*/ +#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS +SQLITE_API int sqlite3_compileoption_used(const char *zOptName); +SQLITE_API const char *sqlite3_compileoption_get(int N); +#else +# define sqlite3_compileoption_used(X) 0 +# define sqlite3_compileoption_get(X) ((void*)0) +#endif + +/* +** CAPI3REF: Test To See If The Library Is Threadsafe +** +** ^The sqlite3_threadsafe() function returns zero if and only if +** SQLite was compiled with mutexing code omitted due to the +** [SQLITE_THREADSAFE] compile-time option being set to 0. +** +** SQLite can be compiled with or without mutexes. When +** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes +** are enabled and SQLite is threadsafe. When the +** [SQLITE_THREADSAFE] macro is 0, +** the mutexes are omitted. Without the mutexes, it is not safe +** to use SQLite concurrently from more than one thread. +** +** Enabling mutexes incurs a measurable performance penalty. +** So if speed is of utmost importance, it makes sense to disable +** the mutexes. But for maximum safety, mutexes should be enabled. +** ^The default behavior is for mutexes to be enabled. +** +** This interface can be used by an application to make sure that the +** version of SQLite that it is linking against was compiled with +** the desired setting of the [SQLITE_THREADSAFE] macro. +** +** This interface only reports on the compile-time mutex setting +** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with +** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but +** can be fully or partially disabled using a call to [sqlite3_config()] +** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], +** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the +** sqlite3_threadsafe() function shows only the compile-time setting of +** thread safety, not any run-time changes to that setting made by +** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() +** is unchanged by calls to sqlite3_config().)^ +** +** See the [threading mode] documentation for additional information. +*/ +SQLITE_API int sqlite3_threadsafe(void); + +/* +** CAPI3REF: Database Connection Handle +** KEYWORDS: {database connection} {database connections} +** +** Each open SQLite database is represented by a pointer to an instance of +** the opaque structure named "sqlite3". It is useful to think of an sqlite3 +** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and +** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] +** and [sqlite3_close_v2()] are its destructors. There are many other +** interfaces (such as +** [sqlite3_prepare_v2()], [sqlite3_create_function()], and +** [sqlite3_busy_timeout()] to name but three) that are methods on an +** sqlite3 object. +*/ +typedef struct sqlite3 sqlite3; + +/* +** CAPI3REF: 64-Bit Integer Types +** KEYWORDS: sqlite_int64 sqlite_uint64 +** +** Because there is no cross-platform way to specify 64-bit integer types +** SQLite includes typedefs for 64-bit signed and unsigned integers. +** +** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. +** The sqlite_int64 and sqlite_uint64 types are supported for backwards +** compatibility only. +** +** ^The sqlite3_int64 and sqlite_int64 types can store integer values +** between -9223372036854775808 and +9223372036854775807 inclusive. ^The +** sqlite3_uint64 and sqlite_uint64 types can store integer values +** between 0 and +18446744073709551615 inclusive. +*/ +#ifdef SQLITE_INT64_TYPE + typedef SQLITE_INT64_TYPE sqlite_int64; +# ifdef SQLITE_UINT64_TYPE + typedef SQLITE_UINT64_TYPE sqlite_uint64; +# else + typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; +# endif +#elif defined(_MSC_VER) || defined(__BORLANDC__) + typedef __int64 sqlite_int64; + typedef unsigned __int64 sqlite_uint64; +#else + typedef long long int sqlite_int64; + typedef unsigned long long int sqlite_uint64; +#endif +typedef sqlite_int64 sqlite3_int64; +typedef sqlite_uint64 sqlite3_uint64; + +/* +** If compiling for a processor that lacks floating point support, +** substitute integer for floating-point. +*/ +#ifdef SQLITE_OMIT_FLOATING_POINT +# define double sqlite3_int64 +#endif + +/* +** CAPI3REF: Closing A Database Connection +** DESTRUCTOR: sqlite3 +** +** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors +** for the [sqlite3] object. +** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if +** the [sqlite3] object is successfully destroyed and all associated +** resources are deallocated. +** +** Ideally, applications should [sqlite3_finalize | finalize] all +** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and +** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated +** with the [sqlite3] object prior to attempting to close the object. +** ^If the database connection is associated with unfinalized prepared +** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then +** sqlite3_close() will leave the database connection open and return +** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared +** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, +** it returns [SQLITE_OK] regardless, but instead of deallocating the database +** connection immediately, it marks the database connection as an unusable +** "zombie" and makes arrangements to automatically deallocate the database +** connection after all prepared statements are finalized, all BLOB handles +** are closed, and all backups have finished. The sqlite3_close_v2() interface +** is intended for use with host languages that are garbage collected, and +** where the order in which destructors are called is arbitrary. +** +** ^If an [sqlite3] object is destroyed while a transaction is open, +** the transaction is automatically rolled back. +** +** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] +** must be either a NULL +** pointer or an [sqlite3] object pointer obtained +** from [sqlite3_open()], [sqlite3_open16()], or +** [sqlite3_open_v2()], and not previously closed. +** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer +** argument is a harmless no-op. +*/ +SQLITE_API int sqlite3_close(sqlite3*); +SQLITE_API int sqlite3_close_v2(sqlite3*); + +/* +** The type for a callback function. +** This is legacy and deprecated. It is included for historical +** compatibility and is not documented. +*/ +typedef int (*sqlite3_callback)(void*,int,char**, char**); + +/* +** CAPI3REF: One-Step Query Execution Interface +** METHOD: sqlite3 +** +** The sqlite3_exec() interface is a convenience wrapper around +** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], +** that allows an application to run multiple statements of SQL +** without having to use a lot of C code. +** +** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, +** semicolon-separate SQL statements passed into its 2nd argument, +** in the context of the [database connection] passed in as its 1st +** argument. ^If the callback function of the 3rd argument to +** sqlite3_exec() is not NULL, then it is invoked for each result row +** coming out of the evaluated SQL statements. ^The 4th argument to +** sqlite3_exec() is relayed through to the 1st argument of each +** callback invocation. ^If the callback pointer to sqlite3_exec() +** is NULL, then no callback is ever invoked and result rows are +** ignored. +** +** ^If an error occurs while evaluating the SQL statements passed into +** sqlite3_exec(), then execution of the current statement stops and +** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() +** is not NULL then any error message is written into memory obtained +** from [sqlite3_malloc()] and passed back through the 5th parameter. +** To avoid memory leaks, the application should invoke [sqlite3_free()] +** on error message strings returned through the 5th parameter of +** sqlite3_exec() after the error message string is no longer needed. +** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors +** occur, then sqlite3_exec() sets the pointer in its 5th parameter to +** NULL before returning. +** +** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() +** routine returns SQLITE_ABORT without invoking the callback again and +** without running any subsequent SQL statements. +** +** ^The 2nd argument to the sqlite3_exec() callback function is the +** number of columns in the result. ^The 3rd argument to the sqlite3_exec() +** callback is an array of pointers to strings obtained as if from +** [sqlite3_column_text()], one for each column. ^If an element of a +** result row is NULL then the corresponding string pointer for the +** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the +** sqlite3_exec() callback is an array of pointers to strings where each +** entry represents the name of corresponding result column as obtained +** from [sqlite3_column_name()]. +** +** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer +** to an empty string, or a pointer that contains only whitespace and/or +** SQL comments, then no SQL statements are evaluated and the database +** is not changed. +** +** Restrictions: +** +**
    +**
  • The application must ensure that the 1st parameter to sqlite3_exec() +** is a valid and open [database connection]. +**
  • The application must not close the [database connection] specified by +** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. +**
  • The application must not modify the SQL statement text passed into +** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. +**
  • The application must not dereference the arrays or string pointers +** passed as the 3rd and 4th callback parameters after it returns. +**
+*/ +SQLITE_API int sqlite3_exec( + sqlite3*, /* An open database */ + const char *sql, /* SQL to be evaluated */ + int (*callback)(void*,int,char**,char**), /* Callback function */ + void *, /* 1st argument to callback */ + char **errmsg /* Error msg written here */ +); + +/* +** CAPI3REF: Result Codes +** KEYWORDS: {result code definitions} +** +** Many SQLite functions return an integer result code from the set shown +** here in order to indicate success or failure. +** +** New error codes may be added in future versions of SQLite. +** +** See also: [extended result code definitions] +*/ +#define SQLITE_OK 0 /* Successful result */ +/* beginning-of-error-codes */ +#define SQLITE_ERROR 1 /* Generic error */ +#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ +#define SQLITE_PERM 3 /* Access permission denied */ +#define SQLITE_ABORT 4 /* Callback routine requested an abort */ +#define SQLITE_BUSY 5 /* The database file is locked */ +#define SQLITE_LOCKED 6 /* A table in the database is locked */ +#define SQLITE_NOMEM 7 /* A malloc() failed */ +#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ +#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ +#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ +#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ +#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ +#define SQLITE_FULL 13 /* Insertion failed because database is full */ +#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ +#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ +#define SQLITE_EMPTY 16 /* Internal use only */ +#define SQLITE_SCHEMA 17 /* The database schema changed */ +#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ +#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ +#define SQLITE_MISMATCH 20 /* Data type mismatch */ +#define SQLITE_MISUSE 21 /* Library used incorrectly */ +#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ +#define SQLITE_AUTH 23 /* Authorization denied */ +#define SQLITE_FORMAT 24 /* Not used */ +#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ +#define SQLITE_NOTADB 26 /* File opened that is not a database file */ +#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ +#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ +#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ +#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ +/* end-of-error-codes */ + +/* +** CAPI3REF: Extended Result Codes +** KEYWORDS: {extended result code definitions} +** +** In its default configuration, SQLite API routines return one of 30 integer +** [result codes]. However, experience has shown that many of +** these result codes are too coarse-grained. They do not provide as +** much information about problems as programmers might like. In an effort to +** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] +** and later) include +** support for additional result codes that provide more detailed information +** about errors. These [extended result codes] are enabled or disabled +** on a per database connection basis using the +** [sqlite3_extended_result_codes()] API. Or, the extended code for +** the most recent error can be obtained using +** [sqlite3_extended_errcode()]. +*/ +#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) +#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) +#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) +#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) +#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) +#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) +#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) +#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) +#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) +#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) +#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) +#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) +#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) +#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) +#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) +#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) +#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) +#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) +#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) +#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) +#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) +#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) +#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) +#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) +#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) +#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) +#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) +#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) +#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) +#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) +#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) +#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) +#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) +#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) +#define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) +#define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) +#define SQLITE_IOERR_IN_PAGE (SQLITE_IOERR | (34<<8)) +#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) +#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) +#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) +#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) +#define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) +#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) +#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) +#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) +#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) +#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ +#define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) +#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) +#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) +#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) +#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) +#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) +#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) +#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) +#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) +#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) +#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) +#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) +#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) +#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) +#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) +#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) +#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) +#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) +#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) +#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) +#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) +#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) +#define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8)) +#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) +#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) +#define SQLITE_NOTICE_RBU (SQLITE_NOTICE | (3<<8)) +#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) +#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) +#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) +#define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal use only */ + +/* +** CAPI3REF: Flags For File Open Operations +** +** These bit values are intended for use in the +** 3rd parameter to the [sqlite3_open_v2()] interface and +** in the 4th parameter to the [sqlite3_vfs.xOpen] method. +** +** Only those flags marked as "Ok for sqlite3_open_v2()" may be +** used as the third argument to the [sqlite3_open_v2()] interface. +** The other flags have historically been ignored by sqlite3_open_v2(), +** though future versions of SQLite might change so that an error is +** raised if any of the disallowed bits are passed into sqlite3_open_v2(). +** Applications should not depend on the historical behavior. +** +** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into +** [sqlite3_open_v2()] does *not* cause the underlying database file +** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into +** [sqlite3_open_v2()] has historically be a no-op and might become an +** error in future versions of SQLite. +*/ +#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ +#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ +#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ +#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ +#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ +#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ +#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ +#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ +#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ +#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ +#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ +#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ +#define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */ + +/* Reserved: 0x00F00000 */ +/* Legacy compatibility: */ +#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ + + +/* +** CAPI3REF: Device Characteristics +** +** The xDeviceCharacteristics method of the [sqlite3_io_methods] +** object returns an integer which is a vector of these +** bit values expressing I/O characteristics of the mass storage +** device that holds the file that the [sqlite3_io_methods] +** refers to. +** +** The SQLITE_IOCAP_ATOMIC property means that all writes of +** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values +** mean that writes of blocks that are nnn bytes in size and +** are aligned to an address which is an integer multiple of +** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means +** that when data is appended to a file, the data is appended +** first then the size of the file is extended, never the other +** way around. The SQLITE_IOCAP_SEQUENTIAL property means that +** information is written to disk in the same order as calls +** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that +** after reboot following a crash or power loss, the only bytes in a +** file that were written at the application level might have changed +** and that adjacent bytes, even bytes within the same sector are +** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN +** flag indicates that a file cannot be deleted when open. The +** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on +** read-only media and cannot be changed even by processes with +** elevated privileges. +** +** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying +** filesystem supports doing multiple write operations atomically when those +** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and +** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. +*/ +#define SQLITE_IOCAP_ATOMIC 0x00000001 +#define SQLITE_IOCAP_ATOMIC512 0x00000002 +#define SQLITE_IOCAP_ATOMIC1K 0x00000004 +#define SQLITE_IOCAP_ATOMIC2K 0x00000008 +#define SQLITE_IOCAP_ATOMIC4K 0x00000010 +#define SQLITE_IOCAP_ATOMIC8K 0x00000020 +#define SQLITE_IOCAP_ATOMIC16K 0x00000040 +#define SQLITE_IOCAP_ATOMIC32K 0x00000080 +#define SQLITE_IOCAP_ATOMIC64K 0x00000100 +#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 +#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 +#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 +#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 +#define SQLITE_IOCAP_IMMUTABLE 0x00002000 +#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 + +/* +** CAPI3REF: File Locking Levels +** +** SQLite uses one of these integer values as the second +** argument to calls it makes to the xLock() and xUnlock() methods +** of an [sqlite3_io_methods] object. These values are ordered from +** lest restrictive to most restrictive. +** +** The argument to xLock() is always SHARED or higher. The argument to +** xUnlock is either SHARED or NONE. +*/ +#define SQLITE_LOCK_NONE 0 /* xUnlock() only */ +#define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */ +#define SQLITE_LOCK_RESERVED 2 /* xLock() only */ +#define SQLITE_LOCK_PENDING 3 /* xLock() only */ +#define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */ + +/* +** CAPI3REF: Synchronization Type Flags +** +** When SQLite invokes the xSync() method of an +** [sqlite3_io_methods] object it uses a combination of +** these integer values as the second argument. +** +** When the SQLITE_SYNC_DATAONLY flag is used, it means that the +** sync operation only needs to flush data to mass storage. Inode +** information need not be flushed. If the lower four bits of the flag +** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. +** If the lower four bits equal SQLITE_SYNC_FULL, that means +** to use Mac OS X style fullsync instead of fsync(). +** +** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags +** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL +** settings. The [synchronous pragma] determines when calls to the +** xSync VFS method occur and applies uniformly across all platforms. +** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how +** energetic or rigorous or forceful the sync operations are and +** only make a difference on Mac OSX for the default SQLite code. +** (Third-party VFS implementations might also make the distinction +** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the +** operating systems natively supported by SQLite, only Mac OSX +** cares about the difference.) +*/ +#define SQLITE_SYNC_NORMAL 0x00002 +#define SQLITE_SYNC_FULL 0x00003 +#define SQLITE_SYNC_DATAONLY 0x00010 + +/* +** CAPI3REF: OS Interface Open File Handle +** +** An [sqlite3_file] object represents an open file in the +** [sqlite3_vfs | OS interface layer]. Individual OS interface +** implementations will +** want to subclass this object by appending additional fields +** for their own use. The pMethods entry is a pointer to an +** [sqlite3_io_methods] object that defines methods for performing +** I/O operations on the open file. +*/ +typedef struct sqlite3_file sqlite3_file; +struct sqlite3_file { + const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ +}; + +/* +** CAPI3REF: OS Interface File Virtual Methods Object +** +** Every file opened by the [sqlite3_vfs.xOpen] method populates an +** [sqlite3_file] object (or, more commonly, a subclass of the +** [sqlite3_file] object) with a pointer to an instance of this object. +** This object defines the methods used to perform various operations +** against the open file represented by the [sqlite3_file] object. +** +** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element +** to a non-NULL pointer, then the sqlite3_io_methods.xClose method +** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The +** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] +** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element +** to NULL. +** +** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or +** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). +** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] +** flag may be ORed in to indicate that only the data of the file +** and not its inode needs to be synced. +** +** The integer values to xLock() and xUnlock() are one of +**
    +**
  • [SQLITE_LOCK_NONE], +**
  • [SQLITE_LOCK_SHARED], +**
  • [SQLITE_LOCK_RESERVED], +**
  • [SQLITE_LOCK_PENDING], or +**
  • [SQLITE_LOCK_EXCLUSIVE]. +**
+** xLock() upgrades the database file lock. In other words, xLock() moves the +** database file lock in the direction NONE toward EXCLUSIVE. The argument to +** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never +** SQLITE_LOCK_NONE. If the database file lock is already at or above the +** requested lock, then the call to xLock() is a no-op. +** xUnlock() downgrades the database file lock to either SHARED or NONE. +** If the lock is already at or below the requested lock state, then the call +** to xUnlock() is a no-op. +** The xCheckReservedLock() method checks whether any database connection, +** either in this process or in some other process, is holding a RESERVED, +** PENDING, or EXCLUSIVE lock on the file. It returns true +** if such a lock exists and false otherwise. +** +** The xFileControl() method is a generic interface that allows custom +** VFS implementations to directly control an open file using the +** [sqlite3_file_control()] interface. The second "op" argument is an +** integer opcode. The third argument is a generic pointer intended to +** point to a structure that may contain arguments or space in which to +** write return values. Potential uses for xFileControl() might be +** functions to enable blocking locks with timeouts, to change the +** locking strategy (for example to use dot-file locks), to inquire +** about the status of a lock, or to break stale locks. The SQLite +** core reserves all opcodes less than 100 for its own use. +** A [file control opcodes | list of opcodes] less than 100 is available. +** Applications that define a custom xFileControl method should use opcodes +** greater than 100 to avoid conflicts. VFS implementations should +** return [SQLITE_NOTFOUND] for file control opcodes that they do not +** recognize. +** +** The xSectorSize() method returns the sector size of the +** device that underlies the file. The sector size is the +** minimum write that can be performed without disturbing +** other bytes in the file. The xDeviceCharacteristics() +** method returns a bit vector describing behaviors of the +** underlying device: +** +**
    +**
  • [SQLITE_IOCAP_ATOMIC] +**
  • [SQLITE_IOCAP_ATOMIC512] +**
  • [SQLITE_IOCAP_ATOMIC1K] +**
  • [SQLITE_IOCAP_ATOMIC2K] +**
  • [SQLITE_IOCAP_ATOMIC4K] +**
  • [SQLITE_IOCAP_ATOMIC8K] +**
  • [SQLITE_IOCAP_ATOMIC16K] +**
  • [SQLITE_IOCAP_ATOMIC32K] +**
  • [SQLITE_IOCAP_ATOMIC64K] +**
  • [SQLITE_IOCAP_SAFE_APPEND] +**
  • [SQLITE_IOCAP_SEQUENTIAL] +**
  • [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] +**
  • [SQLITE_IOCAP_POWERSAFE_OVERWRITE] +**
  • [SQLITE_IOCAP_IMMUTABLE] +**
  • [SQLITE_IOCAP_BATCH_ATOMIC] +**
+** +** The SQLITE_IOCAP_ATOMIC property means that all writes of +** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values +** mean that writes of blocks that are nnn bytes in size and +** are aligned to an address which is an integer multiple of +** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means +** that when data is appended to a file, the data is appended +** first then the size of the file is extended, never the other +** way around. The SQLITE_IOCAP_SEQUENTIAL property means that +** information is written to disk in the same order as calls +** to xWrite(). +** +** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill +** in the unread portions of the buffer with zeros. A VFS that +** fails to zero-fill short reads might seem to work. However, +** failure to zero-fill short reads will eventually lead to +** database corruption. +*/ +typedef struct sqlite3_io_methods sqlite3_io_methods; +struct sqlite3_io_methods { + int iVersion; + int (*xClose)(sqlite3_file*); + int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); + int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); + int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); + int (*xSync)(sqlite3_file*, int flags); + int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); + int (*xLock)(sqlite3_file*, int); + int (*xUnlock)(sqlite3_file*, int); + int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); + int (*xFileControl)(sqlite3_file*, int op, void *pArg); + int (*xSectorSize)(sqlite3_file*); + int (*xDeviceCharacteristics)(sqlite3_file*); + /* Methods above are valid for version 1 */ + int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); + int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); + void (*xShmBarrier)(sqlite3_file*); + int (*xShmUnmap)(sqlite3_file*, int deleteFlag); + /* Methods above are valid for version 2 */ + int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); + int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); + /* Methods above are valid for version 3 */ + /* Additional methods may be added in future releases */ +}; + +/* +** CAPI3REF: Standard File Control Opcodes +** KEYWORDS: {file control opcodes} {file control opcode} +** +** These integer constants are opcodes for the xFileControl method +** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] +** interface. +** +**
    +**
  • [[SQLITE_FCNTL_LOCKSTATE]] +** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This +** opcode causes the xFileControl method to write the current state of +** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], +** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) +** into an integer that the pArg argument points to. +** This capability is only available if SQLite is compiled with [SQLITE_DEBUG]. +** +**
  • [[SQLITE_FCNTL_SIZE_HINT]] +** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS +** layer a hint of how large the database file will grow to be during the +** current transaction. This hint is not guaranteed to be accurate but it +** is often close. The underlying VFS might choose to preallocate database +** file space based on this hint in order to help writes to the database +** file run faster. +** +**
  • [[SQLITE_FCNTL_SIZE_LIMIT]] +** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that +** implements [sqlite3_deserialize()] to set an upper bound on the size +** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. +** If the integer pointed to is negative, then it is filled in with the +** current limit. Otherwise the limit is set to the larger of the value +** of the integer pointed to and the current database size. The integer +** pointed to is set to the new limit. +** +**
  • [[SQLITE_FCNTL_CHUNK_SIZE]] +** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS +** extends and truncates the database file in chunks of a size specified +** by the user. The fourth argument to [sqlite3_file_control()] should +** point to an integer (type int) containing the new chunk-size to use +** for the nominated database. Allocating database file space in large +** chunks (say 1MB at a time), may reduce file-system fragmentation and +** improve performance on some systems. +** +**
  • [[SQLITE_FCNTL_FILE_POINTER]] +** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer +** to the [sqlite3_file] object associated with a particular database +** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. +** +**
  • [[SQLITE_FCNTL_JOURNAL_POINTER]] +** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer +** to the [sqlite3_file] object associated with the journal file (either +** the [rollback journal] or the [write-ahead log]) for a particular database +** connection. See also [SQLITE_FCNTL_FILE_POINTER]. +** +**
  • [[SQLITE_FCNTL_SYNC_OMITTED]] +** No longer in use. +** +**
  • [[SQLITE_FCNTL_SYNC]] +** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and +** sent to the VFS immediately before the xSync method is invoked on a +** database file descriptor. Or, if the xSync method is not invoked +** because the user has configured SQLite with +** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place +** of the xSync method. In most cases, the pointer argument passed with +** this file-control is NULL. However, if the database file is being synced +** as part of a multi-database commit, the argument points to a nul-terminated +** string containing the transactions super-journal file name. VFSes that +** do not need this signal should silently ignore this opcode. Applications +** should not call [sqlite3_file_control()] with this opcode as doing so may +** disrupt the operation of the specialized VFSes that do require it. +** +**
  • [[SQLITE_FCNTL_COMMIT_PHASETWO]] +** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite +** and sent to the VFS after a transaction has been committed immediately +** but before the database is unlocked. VFSes that do not need this signal +** should silently ignore this opcode. Applications should not call +** [sqlite3_file_control()] with this opcode as doing so may disrupt the +** operation of the specialized VFSes that do require it. +** +**
  • [[SQLITE_FCNTL_WIN32_AV_RETRY]] +** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic +** retry counts and intervals for certain disk I/O operations for the +** windows [VFS] in order to provide robustness in the presence of +** anti-virus programs. By default, the windows VFS will retry file read, +** file write, and file delete operations up to 10 times, with a delay +** of 25 milliseconds before the first retry and with the delay increasing +** by an additional 25 milliseconds with each subsequent retry. This +** opcode allows these two values (10 retries and 25 milliseconds of delay) +** to be adjusted. The values are changed for all database connections +** within the same process. The argument is a pointer to an array of two +** integers where the first integer is the new retry count and the second +** integer is the delay. If either integer is negative, then the setting +** is not changed but instead the prior value of that setting is written +** into the array entry, allowing the current retry settings to be +** interrogated. The zDbName parameter is ignored. +** +**
  • [[SQLITE_FCNTL_PERSIST_WAL]] +** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the +** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary +** write ahead log ([WAL file]) and shared memory +** files used for transaction control +** are automatically deleted when the latest connection to the database +** closes. Setting persistent WAL mode causes those files to persist after +** close. Persisting the files is useful when other processes that do not +** have write permission on the directory containing the database file want +** to read the database file, as the WAL and shared memory files must exist +** in order for the database to be readable. The fourth parameter to +** [sqlite3_file_control()] for this opcode should be a pointer to an integer. +** That integer is 0 to disable persistent WAL mode or 1 to enable persistent +** WAL mode. If the integer is -1, then it is overwritten with the current +** WAL persistence setting. +** +**
  • [[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] +** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the +** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting +** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the +** xDeviceCharacteristics methods. The fourth parameter to +** [sqlite3_file_control()] for this opcode should be a pointer to an integer. +** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage +** mode. If the integer is -1, then it is overwritten with the current +** zero-damage mode setting. +** +**
  • [[SQLITE_FCNTL_OVERWRITE]] +** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening +** a write transaction to indicate that, unless it is rolled back for some +** reason, the entire database file will be overwritten by the current +** transaction. This is used by VACUUM operations. +** +**
  • [[SQLITE_FCNTL_VFSNAME]] +** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of +** all [VFSes] in the VFS stack. The names are of all VFS shims and the +** final bottom-level VFS are written into memory obtained from +** [sqlite3_malloc()] and the result is stored in the char* variable +** that the fourth parameter of [sqlite3_file_control()] points to. +** The caller is responsible for freeing the memory when done. As with +** all file-control actions, there is no guarantee that this will actually +** do anything. Callers should initialize the char* variable to a NULL +** pointer in case this file-control is not implemented. This file-control +** is intended for diagnostic use only. +** +**
  • [[SQLITE_FCNTL_VFS_POINTER]] +** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level +** [VFSes] currently in use. ^(The argument X in +** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be +** of type "[sqlite3_vfs] **". This opcodes will set *X +** to a pointer to the top-level VFS.)^ +** ^When there are multiple VFS shims in the stack, this opcode finds the +** upper-most shim only. +** +**
  • [[SQLITE_FCNTL_PRAGMA]] +** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] +** file control is sent to the open [sqlite3_file] object corresponding +** to the database file to which the pragma statement refers. ^The argument +** to the [SQLITE_FCNTL_PRAGMA] file control is an array of +** pointers to strings (char**) in which the second element of the array +** is the name of the pragma and the third element is the argument to the +** pragma or NULL if the pragma has no argument. ^The handler for an +** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element +** of the char** argument point to a string obtained from [sqlite3_mprintf()] +** or the equivalent and that string will become the result of the pragma or +** the error message if the pragma fails. ^If the +** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal +** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] +** file control returns [SQLITE_OK], then the parser assumes that the +** VFS has handled the PRAGMA itself and the parser generates a no-op +** prepared statement if result string is NULL, or that returns a copy +** of the result string if the string is non-NULL. +** ^If the [SQLITE_FCNTL_PRAGMA] file control returns +** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means +** that the VFS encountered an error while handling the [PRAGMA] and the +** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] +** file control occurs at the beginning of pragma statement analysis and so +** it is able to override built-in [PRAGMA] statements. +** +**
  • [[SQLITE_FCNTL_BUSYHANDLER]] +** ^The [SQLITE_FCNTL_BUSYHANDLER] +** file-control may be invoked by SQLite on the database file handle +** shortly after it is opened in order to provide a custom VFS with access +** to the connection's busy-handler callback. The argument is of type (void**) +** - an array of two (void *) values. The first (void *) actually points +** to a function of type (int (*)(void *)). In order to invoke the connection's +** busy-handler, this function should be invoked with the second (void *) in +** the array as the only argument. If it returns non-zero, then the operation +** should be retried. If it returns zero, the custom VFS should abandon the +** current operation. +** +**
  • [[SQLITE_FCNTL_TEMPFILENAME]] +** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control +** to have SQLite generate a +** temporary filename using the same algorithm that is followed to generate +** temporary filenames for TEMP tables and other internal uses. The +** argument should be a char** which will be filled with the filename +** written into memory obtained from [sqlite3_malloc()]. The caller should +** invoke [sqlite3_free()] on the result to avoid a memory leak. +** +**
  • [[SQLITE_FCNTL_MMAP_SIZE]] +** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the +** maximum number of bytes that will be used for memory-mapped I/O. +** The argument is a pointer to a value of type sqlite3_int64 that +** is an advisory maximum number of bytes in the file to memory map. The +** pointer is overwritten with the old value. The limit is not changed if +** the value originally pointed to is negative, and so the current limit +** can be queried by passing in a pointer to a negative number. This +** file-control is used internally to implement [PRAGMA mmap_size]. +** +**
  • [[SQLITE_FCNTL_TRACE]] +** The [SQLITE_FCNTL_TRACE] file control provides advisory information +** to the VFS about what the higher layers of the SQLite stack are doing. +** This file control is used by some VFS activity tracing [shims]. +** The argument is a zero-terminated string. Higher layers in the +** SQLite stack may generate instances of this file control if +** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. +** +**
  • [[SQLITE_FCNTL_HAS_MOVED]] +** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a +** pointer to an integer and it writes a boolean into that integer depending +** on whether or not the file has been renamed, moved, or deleted since it +** was first opened. +** +**
  • [[SQLITE_FCNTL_WIN32_GET_HANDLE]] +** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the +** underlying native file handle associated with a file handle. This file +** control interprets its argument as a pointer to a native file handle and +** writes the resulting value there. +** +**
  • [[SQLITE_FCNTL_WIN32_SET_HANDLE]] +** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This +** opcode causes the xFileControl method to swap the file handle with the one +** pointed to by the pArg argument. This capability is used during testing +** and only needs to be supported when SQLITE_TEST is defined. +** +**
  • [[SQLITE_FCNTL_WAL_BLOCK]] +** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might +** be advantageous to block on the next WAL lock if the lock is not immediately +** available. The WAL subsystem issues this signal during rare +** circumstances in order to fix a problem with priority inversion. +** Applications should not use this file-control. +** +**
  • [[SQLITE_FCNTL_ZIPVFS]] +** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other +** VFS should return SQLITE_NOTFOUND for this opcode. +** +**
  • [[SQLITE_FCNTL_RBU]] +** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by +** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for +** this opcode. +** +**
  • [[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] +** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then +** the file descriptor is placed in "batch write mode", which +** means all subsequent write operations will be deferred and done +** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems +** that do not support batch atomic writes will return SQLITE_NOTFOUND. +** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to +** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or +** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make +** no VFS interface calls on the same [sqlite3_file] file descriptor +** except for calls to the xWrite method and the xFileControl method +** with [SQLITE_FCNTL_SIZE_HINT]. +** +**
  • [[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] +** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write +** operations since the previous successful call to +** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. +** This file control returns [SQLITE_OK] if and only if the writes were +** all performed successfully and have been committed to persistent storage. +** ^Regardless of whether or not it is successful, this file control takes +** the file descriptor out of batch write mode so that all subsequent +** write operations are independent. +** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without +** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. +** +**
  • [[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] +** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write +** operations since the previous successful call to +** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. +** ^This file control takes the file descriptor out of batch write mode +** so that all subsequent write operations are independent. +** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without +** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. +** +**
  • [[SQLITE_FCNTL_LOCK_TIMEOUT]] +** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS +** to block for up to M milliseconds before failing when attempting to +** obtain a file lock using the xLock or xShmLock methods of the VFS. +** The parameter is a pointer to a 32-bit signed integer that contains +** the value that M is to be set to. Before returning, the 32-bit signed +** integer is overwritten with the previous value of M. +** +**
  • [[SQLITE_FCNTL_DATA_VERSION]] +** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to +** a database file. The argument is a pointer to a 32-bit unsigned integer. +** The "data version" for the pager is written into the pointer. The +** "data version" changes whenever any change occurs to the corresponding +** database file, either through SQL statements on the same database +** connection or through transactions committed by separate database +** connections possibly in other processes. The [sqlite3_total_changes()] +** interface can be used to find if any database on the connection has changed, +** but that interface responds to changes on TEMP as well as MAIN and does +** not provide a mechanism to detect changes to MAIN only. Also, the +** [sqlite3_total_changes()] interface responds to internal changes only and +** omits changes made by other database connections. The +** [PRAGMA data_version] command provides a mechanism to detect changes to +** a single attached database that occur due to other database connections, +** but omits changes implemented by the database connection on which it is +** called. This file control is the only mechanism to detect changes that +** happen either internally or externally and that are associated with +** a particular attached database. +** +**
  • [[SQLITE_FCNTL_CKPT_START]] +** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint +** in wal mode before the client starts to copy pages from the wal +** file to the database file. +** +**
  • [[SQLITE_FCNTL_CKPT_DONE]] +** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint +** in wal mode after the client has finished copying pages from the wal +** file to the database file, but before the *-shm file is updated to +** record the fact that the pages have been checkpointed. +** +**
  • [[SQLITE_FCNTL_EXTERNAL_READER]] +** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect +** whether or not there is a database client in another process with a wal-mode +** transaction open on the database or not. It is only available on unix.The +** (void*) argument passed with this file-control should be a pointer to a +** value of type (int). The integer value is set to 1 if the database is a wal +** mode database and there exists at least one client in another process that +** currently has an SQL transaction open on the database. It is set to 0 if +** the database is not a wal-mode db, or if there is no such connection in any +** other process. This opcode cannot be used to detect transactions opened +** by clients within the current process, only within other processes. +** +**
  • [[SQLITE_FCNTL_CKSM_FILE]] +** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the +** [checksum VFS shim] only. +** +**
  • [[SQLITE_FCNTL_RESET_CACHE]] +** If there is currently no transaction open on the database, and the +** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control +** purges the contents of the in-memory page cache. If there is an open +** transaction, or if the db is a temp-db, this opcode is a no-op, not an error. +**
+*/ +#define SQLITE_FCNTL_LOCKSTATE 1 +#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 +#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 +#define SQLITE_FCNTL_LAST_ERRNO 4 +#define SQLITE_FCNTL_SIZE_HINT 5 +#define SQLITE_FCNTL_CHUNK_SIZE 6 +#define SQLITE_FCNTL_FILE_POINTER 7 +#define SQLITE_FCNTL_SYNC_OMITTED 8 +#define SQLITE_FCNTL_WIN32_AV_RETRY 9 +#define SQLITE_FCNTL_PERSIST_WAL 10 +#define SQLITE_FCNTL_OVERWRITE 11 +#define SQLITE_FCNTL_VFSNAME 12 +#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 +#define SQLITE_FCNTL_PRAGMA 14 +#define SQLITE_FCNTL_BUSYHANDLER 15 +#define SQLITE_FCNTL_TEMPFILENAME 16 +#define SQLITE_FCNTL_MMAP_SIZE 18 +#define SQLITE_FCNTL_TRACE 19 +#define SQLITE_FCNTL_HAS_MOVED 20 +#define SQLITE_FCNTL_SYNC 21 +#define SQLITE_FCNTL_COMMIT_PHASETWO 22 +#define SQLITE_FCNTL_WIN32_SET_HANDLE 23 +#define SQLITE_FCNTL_WAL_BLOCK 24 +#define SQLITE_FCNTL_ZIPVFS 25 +#define SQLITE_FCNTL_RBU 26 +#define SQLITE_FCNTL_VFS_POINTER 27 +#define SQLITE_FCNTL_JOURNAL_POINTER 28 +#define SQLITE_FCNTL_WIN32_GET_HANDLE 29 +#define SQLITE_FCNTL_PDB 30 +#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 +#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 +#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 +#define SQLITE_FCNTL_LOCK_TIMEOUT 34 +#define SQLITE_FCNTL_DATA_VERSION 35 +#define SQLITE_FCNTL_SIZE_LIMIT 36 +#define SQLITE_FCNTL_CKPT_DONE 37 +#define SQLITE_FCNTL_RESERVE_BYTES 38 +#define SQLITE_FCNTL_CKPT_START 39 +#define SQLITE_FCNTL_EXTERNAL_READER 40 +#define SQLITE_FCNTL_CKSM_FILE 41 +#define SQLITE_FCNTL_RESET_CACHE 42 + +/* deprecated names */ +#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE +#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE +#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO + + +/* +** CAPI3REF: Mutex Handle +** +** The mutex module within SQLite defines [sqlite3_mutex] to be an +** abstract type for a mutex object. The SQLite core never looks +** at the internal representation of an [sqlite3_mutex]. It only +** deals with pointers to the [sqlite3_mutex] object. +** +** Mutexes are created using [sqlite3_mutex_alloc()]. +*/ +typedef struct sqlite3_mutex sqlite3_mutex; + +/* +** CAPI3REF: Loadable Extension Thunk +** +** A pointer to the opaque sqlite3_api_routines structure is passed as +** the third parameter to entry points of [loadable extensions]. This +** structure must be typedefed in order to work around compiler warnings +** on some platforms. +*/ +typedef struct sqlite3_api_routines sqlite3_api_routines; + +/* +** CAPI3REF: File Name +** +** Type [sqlite3_filename] is used by SQLite to pass filenames to the +** xOpen method of a [VFS]. It may be cast to (const char*) and treated +** as a normal, nul-terminated, UTF-8 buffer containing the filename, but +** may also be passed to special APIs such as: +** +**
    +**
  • sqlite3_filename_database() +**
  • sqlite3_filename_journal() +**
  • sqlite3_filename_wal() +**
  • sqlite3_uri_parameter() +**
  • sqlite3_uri_boolean() +**
  • sqlite3_uri_int64() +**
  • sqlite3_uri_key() +**
+*/ +typedef const char *sqlite3_filename; + +/* +** CAPI3REF: OS Interface Object +** +** An instance of the sqlite3_vfs object defines the interface between +** the SQLite core and the underlying operating system. The "vfs" +** in the name of the object stands for "virtual file system". See +** the [VFS | VFS documentation] for further information. +** +** The VFS interface is sometimes extended by adding new methods onto +** the end. Each time such an extension occurs, the iVersion field +** is incremented. The iVersion value started out as 1 in +** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 +** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased +** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields +** may be appended to the sqlite3_vfs object and the iVersion value +** may increase again in future versions of SQLite. +** Note that due to an oversight, the structure +** of the sqlite3_vfs object changed in the transition from +** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] +** and yet the iVersion field was not increased. +** +** The szOsFile field is the size of the subclassed [sqlite3_file] +** structure used by this VFS. mxPathname is the maximum length of +** a pathname in this VFS. +** +** Registered sqlite3_vfs objects are kept on a linked list formed by +** the pNext pointer. The [sqlite3_vfs_register()] +** and [sqlite3_vfs_unregister()] interfaces manage this list +** in a thread-safe way. The [sqlite3_vfs_find()] interface +** searches the list. Neither the application code nor the VFS +** implementation should use the pNext pointer. +** +** The pNext field is the only field in the sqlite3_vfs +** structure that SQLite will ever modify. SQLite will only access +** or modify this field while holding a particular static mutex. +** The application should never modify anything within the sqlite3_vfs +** object once the object has been registered. +** +** The zName field holds the name of the VFS module. The name must +** be unique across all VFS modules. +** +** [[sqlite3_vfs.xOpen]] +** ^SQLite guarantees that the zFilename parameter to xOpen +** is either a NULL pointer or string obtained +** from xFullPathname() with an optional suffix added. +** ^If a suffix is added to the zFilename parameter, it will +** consist of a single "-" character followed by no more than +** 11 alphanumeric and/or "-" characters. +** ^SQLite further guarantees that +** the string will be valid and unchanged until xClose() is +** called. Because of the previous sentence, +** the [sqlite3_file] can safely store a pointer to the +** filename if it needs to remember the filename for some reason. +** If the zFilename parameter to xOpen is a NULL pointer then xOpen +** must invent its own temporary name for the file. ^Whenever the +** xFilename parameter is NULL it will also be the case that the +** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. +** +** The flags argument to xOpen() includes all bits set in +** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] +** or [sqlite3_open16()] is used, then flags includes at least +** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. +** If xOpen() opens a file read-only then it sets *pOutFlags to +** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. +** +** ^(SQLite will also add one of the following flags to the xOpen() +** call, depending on the object being opened: +** +**
    +**
  • [SQLITE_OPEN_MAIN_DB] +**
  • [SQLITE_OPEN_MAIN_JOURNAL] +**
  • [SQLITE_OPEN_TEMP_DB] +**
  • [SQLITE_OPEN_TEMP_JOURNAL] +**
  • [SQLITE_OPEN_TRANSIENT_DB] +**
  • [SQLITE_OPEN_SUBJOURNAL] +**
  • [SQLITE_OPEN_SUPER_JOURNAL] +**
  • [SQLITE_OPEN_WAL] +**
)^ +** +** The file I/O implementation can use the object type flags to +** change the way it deals with files. For example, an application +** that does not care about crash recovery or rollback might make +** the open of a journal file a no-op. Writes to this journal would +** also be no-ops, and any attempt to read the journal would return +** SQLITE_IOERR. Or the implementation might recognize that a database +** file will be doing page-aligned sector reads and writes in a random +** order and set up its I/O subsystem accordingly. +** +** SQLite might also add one of the following flags to the xOpen method: +** +**
    +**
  • [SQLITE_OPEN_DELETEONCLOSE] +**
  • [SQLITE_OPEN_EXCLUSIVE] +**
+** +** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be +** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] +** will be set for TEMP databases and their journals, transient +** databases, and subjournals. +** +** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction +** with the [SQLITE_OPEN_CREATE] flag, which are both directly +** analogous to the O_EXCL and O_CREAT flags of the POSIX open() +** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the +** SQLITE_OPEN_CREATE, is used to indicate that file should always +** be created, and that it is an error if it already exists. +** It is not used to indicate the file should be opened +** for exclusive access. +** +** ^At least szOsFile bytes of memory are allocated by SQLite +** to hold the [sqlite3_file] structure passed as the third +** argument to xOpen. The xOpen method does not have to +** allocate the structure; it should just fill it in. Note that +** the xOpen method must set the sqlite3_file.pMethods to either +** a valid [sqlite3_io_methods] object or to NULL. xOpen must do +** this even if the open fails. SQLite expects that the sqlite3_file.pMethods +** element will be valid after xOpen returns regardless of the success +** or failure of the xOpen call. +** +** [[sqlite3_vfs.xAccess]] +** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] +** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to +** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] +** to test whether a file is at least readable. The SQLITE_ACCESS_READ +** flag is never actually used and is not implemented in the built-in +** VFSes of SQLite. The file is named by the second argument and can be a +** directory. The xAccess method returns [SQLITE_OK] on success or some +** non-zero error code if there is an I/O error or if the name of +** the file given in the second argument is illegal. If SQLITE_OK +** is returned, then non-zero or zero is written into *pResOut to indicate +** whether or not the file is accessible. +** +** ^SQLite will always allocate at least mxPathname+1 bytes for the +** output buffer xFullPathname. The exact size of the output buffer +** is also passed as a parameter to both methods. If the output buffer +** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is +** handled as a fatal error by SQLite, vfs implementations should endeavor +** to prevent this by setting mxPathname to a sufficiently large value. +** +** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() +** interfaces are not strictly a part of the filesystem, but they are +** included in the VFS structure for completeness. +** The xRandomness() function attempts to return nBytes bytes +** of good-quality randomness into zOut. The return value is +** the actual number of bytes of randomness obtained. +** The xSleep() method causes the calling thread to sleep for at +** least the number of microseconds given. ^The xCurrentTime() +** method returns a Julian Day Number for the current date and time as +** a floating point value. +** ^The xCurrentTimeInt64() method returns, as an integer, the Julian +** Day Number multiplied by 86400000 (the number of milliseconds in +** a 24-hour day). +** ^SQLite will use the xCurrentTimeInt64() method to get the current +** date and time if that method is available (if iVersion is 2 or +** greater and the function pointer is not NULL) and will fall back +** to xCurrentTime() if xCurrentTimeInt64() is unavailable. +** +** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces +** are not used by the SQLite core. These optional interfaces are provided +** by some VFSes to facilitate testing of the VFS code. By overriding +** system calls with functions under its control, a test program can +** simulate faults and error conditions that would otherwise be difficult +** or impossible to induce. The set of system calls that can be overridden +** varies from one VFS to another, and from one version of the same VFS to the +** next. Applications that use these interfaces must be prepared for any +** or all of these interfaces to be NULL or for their behavior to change +** from one release to the next. Applications must not attempt to access +** any of these methods if the iVersion of the VFS is less than 3. +*/ +typedef struct sqlite3_vfs sqlite3_vfs; +typedef void (*sqlite3_syscall_ptr)(void); +struct sqlite3_vfs { + int iVersion; /* Structure version number (currently 3) */ + int szOsFile; /* Size of subclassed sqlite3_file */ + int mxPathname; /* Maximum file pathname length */ + sqlite3_vfs *pNext; /* Next registered VFS */ + const char *zName; /* Name of this virtual file system */ + void *pAppData; /* Pointer to application-specific data */ + int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*, + int flags, int *pOutFlags); + int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); + int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); + int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); + void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); + void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); + void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); + void (*xDlClose)(sqlite3_vfs*, void*); + int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); + int (*xSleep)(sqlite3_vfs*, int microseconds); + int (*xCurrentTime)(sqlite3_vfs*, double*); + int (*xGetLastError)(sqlite3_vfs*, int, char *); + /* + ** The methods above are in version 1 of the sqlite_vfs object + ** definition. Those that follow are added in version 2 or later + */ + int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); + /* + ** The methods above are in versions 1 and 2 of the sqlite_vfs object. + ** Those below are for version 3 and greater. + */ + int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); + sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); + const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); + /* + ** The methods above are in versions 1 through 3 of the sqlite_vfs object. + ** New fields may be appended in future versions. The iVersion + ** value will increment whenever this happens. + */ +}; + +/* +** CAPI3REF: Flags for the xAccess VFS method +** +** These integer constants can be used as the third parameter to +** the xAccess method of an [sqlite3_vfs] object. They determine +** what kind of permissions the xAccess method is looking for. +** With SQLITE_ACCESS_EXISTS, the xAccess method +** simply checks whether the file exists. +** With SQLITE_ACCESS_READWRITE, the xAccess method +** checks whether the named directory is both readable and writable +** (in other words, if files can be added, removed, and renamed within +** the directory). +** The SQLITE_ACCESS_READWRITE constant is currently used only by the +** [temp_store_directory pragma], though this could change in a future +** release of SQLite. +** With SQLITE_ACCESS_READ, the xAccess method +** checks whether the file is readable. The SQLITE_ACCESS_READ constant is +** currently unused, though it might be used in a future release of +** SQLite. +*/ +#define SQLITE_ACCESS_EXISTS 0 +#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ +#define SQLITE_ACCESS_READ 2 /* Unused */ + +/* +** CAPI3REF: Flags for the xShmLock VFS method +** +** These integer constants define the various locking operations +** allowed by the xShmLock method of [sqlite3_io_methods]. The +** following are the only legal combinations of flags to the +** xShmLock method: +** +**
    +**
  • SQLITE_SHM_LOCK | SQLITE_SHM_SHARED +**
  • SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE +**
  • SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED +**
  • SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE +**
+** +** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as +** was given on the corresponding lock. +** +** The xShmLock method can transition between unlocked and SHARED or +** between unlocked and EXCLUSIVE. It cannot transition between SHARED +** and EXCLUSIVE. +*/ +#define SQLITE_SHM_UNLOCK 1 +#define SQLITE_SHM_LOCK 2 +#define SQLITE_SHM_SHARED 4 +#define SQLITE_SHM_EXCLUSIVE 8 + +/* +** CAPI3REF: Maximum xShmLock index +** +** The xShmLock method on [sqlite3_io_methods] may use values +** between 0 and this upper bound as its "offset" argument. +** The SQLite core will never attempt to acquire or release a +** lock outside of this range +*/ +#define SQLITE_SHM_NLOCK 8 + + +/* +** CAPI3REF: Initialize The SQLite Library +** +** ^The sqlite3_initialize() routine initializes the +** SQLite library. ^The sqlite3_shutdown() routine +** deallocates any resources that were allocated by sqlite3_initialize(). +** These routines are designed to aid in process initialization and +** shutdown on embedded systems. Workstation applications using +** SQLite normally do not need to invoke either of these routines. +** +** A call to sqlite3_initialize() is an "effective" call if it is +** the first time sqlite3_initialize() is invoked during the lifetime of +** the process, or if it is the first time sqlite3_initialize() is invoked +** following a call to sqlite3_shutdown(). ^(Only an effective call +** of sqlite3_initialize() does any initialization. All other calls +** are harmless no-ops.)^ +** +** A call to sqlite3_shutdown() is an "effective" call if it is the first +** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only +** an effective call to sqlite3_shutdown() does any deinitialization. +** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ +** +** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() +** is not. The sqlite3_shutdown() interface must only be called from a +** single thread. All open [database connections] must be closed and all +** other SQLite resources must be deallocated prior to invoking +** sqlite3_shutdown(). +** +** Among other things, ^sqlite3_initialize() will invoke +** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() +** will invoke sqlite3_os_end(). +** +** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. +** ^If for some reason, sqlite3_initialize() is unable to initialize +** the library (perhaps it is unable to allocate a needed resource such +** as a mutex) it returns an [error code] other than [SQLITE_OK]. +** +** ^The sqlite3_initialize() routine is called internally by many other +** SQLite interfaces so that an application usually does not need to +** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] +** calls sqlite3_initialize() so the SQLite library will be automatically +** initialized when [sqlite3_open()] is called if it has not be initialized +** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] +** compile-time option, then the automatic calls to sqlite3_initialize() +** are omitted and the application must call sqlite3_initialize() directly +** prior to using any other SQLite interface. For maximum portability, +** it is recommended that applications always invoke sqlite3_initialize() +** directly prior to using any other SQLite interface. Future releases +** of SQLite may require this. In other words, the behavior exhibited +** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the +** default behavior in some future release of SQLite. +** +** The sqlite3_os_init() routine does operating-system specific +** initialization of the SQLite library. The sqlite3_os_end() +** routine undoes the effect of sqlite3_os_init(). Typical tasks +** performed by these routines include allocation or deallocation +** of static resources, initialization of global variables, +** setting up a default [sqlite3_vfs] module, or setting up +** a default configuration using [sqlite3_config()]. +** +** The application should never invoke either sqlite3_os_init() +** or sqlite3_os_end() directly. The application should only invoke +** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() +** interface is called automatically by sqlite3_initialize() and +** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate +** implementations for sqlite3_os_init() and sqlite3_os_end() +** are built into SQLite when it is compiled for Unix, Windows, or OS/2. +** When [custom builds | built for other platforms] +** (using the [SQLITE_OS_OTHER=1] compile-time +** option) the application must supply a suitable implementation for +** sqlite3_os_init() and sqlite3_os_end(). An application-supplied +** implementation of sqlite3_os_init() or sqlite3_os_end() +** must return [SQLITE_OK] on success and some other [error code] upon +** failure. +*/ +SQLITE_API int sqlite3_initialize(void); +SQLITE_API int sqlite3_shutdown(void); +SQLITE_API int sqlite3_os_init(void); +SQLITE_API int sqlite3_os_end(void); + +/* +** CAPI3REF: Configuring The SQLite Library +** +** The sqlite3_config() interface is used to make global configuration +** changes to SQLite in order to tune SQLite to the specific needs of +** the application. The default configuration is recommended for most +** applications and so this routine is usually not necessary. It is +** provided to support rare applications with unusual needs. +** +** The sqlite3_config() interface is not threadsafe. The application +** must ensure that no other SQLite interfaces are invoked by other +** threads while sqlite3_config() is running. +** +** The first argument to sqlite3_config() is an integer +** [configuration option] that determines +** what property of SQLite is to be configured. Subsequent arguments +** vary depending on the [configuration option] +** in the first argument. +** +** For most configuration options, the sqlite3_config() interface +** may only be invoked prior to library initialization using +** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. +** The exceptional configuration options that may be invoked at any time +** are called "anytime configuration options". +** ^If sqlite3_config() is called after [sqlite3_initialize()] and before +** [sqlite3_shutdown()] with a first argument that is not an anytime +** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE. +** Note, however, that ^sqlite3_config() can be called as part of the +** implementation of an application-defined [sqlite3_os_init()]. +** +** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. +** ^If the option is unknown or SQLite is unable to set the option +** then this routine returns a non-zero [error code]. +*/ +SQLITE_API int sqlite3_config(int, ...); + +/* +** CAPI3REF: Configure database connections +** METHOD: sqlite3 +** +** The sqlite3_db_config() interface is used to make configuration +** changes to a [database connection]. The interface is similar to +** [sqlite3_config()] except that the changes apply to a single +** [database connection] (specified in the first argument). +** +** The second argument to sqlite3_db_config(D,V,...) is the +** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code +** that indicates what aspect of the [database connection] is being configured. +** Subsequent arguments vary depending on the configuration verb. +** +** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if +** the call is considered successful. +*/ +SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); + +/* +** CAPI3REF: Memory Allocation Routines +** +** An instance of this object defines the interface between SQLite +** and low-level memory allocation routines. +** +** This object is used in only one place in the SQLite interface. +** A pointer to an instance of this object is the argument to +** [sqlite3_config()] when the configuration option is +** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. +** By creating an instance of this object +** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) +** during configuration, an application can specify an alternative +** memory allocation subsystem for SQLite to use for all of its +** dynamic memory needs. +** +** Note that SQLite comes with several [built-in memory allocators] +** that are perfectly adequate for the overwhelming majority of applications +** and that this object is only useful to a tiny minority of applications +** with specialized memory allocation requirements. This object is +** also used during testing of SQLite in order to specify an alternative +** memory allocator that simulates memory out-of-memory conditions in +** order to verify that SQLite recovers gracefully from such +** conditions. +** +** The xMalloc, xRealloc, and xFree methods must work like the +** malloc(), realloc() and free() functions from the standard C library. +** ^SQLite guarantees that the second argument to +** xRealloc is always a value returned by a prior call to xRoundup. +** +** xSize should return the allocated size of a memory allocation +** previously obtained from xMalloc or xRealloc. The allocated size +** is always at least as big as the requested size but may be larger. +** +** The xRoundup method returns what would be the allocated size of +** a memory allocation given a particular requested size. Most memory +** allocators round up memory allocations at least to the next multiple +** of 8. Some allocators round up to a larger multiple or to a power of 2. +** Every memory allocation request coming in through [sqlite3_malloc()] +** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, +** that causes the corresponding memory allocation to fail. +** +** The xInit method initializes the memory allocator. For example, +** it might allocate any required mutexes or initialize internal data +** structures. The xShutdown method is invoked (indirectly) by +** [sqlite3_shutdown()] and should deallocate any resources acquired +** by xInit. The pAppData pointer is used as the only parameter to +** xInit and xShutdown. +** +** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes +** the xInit method, so the xInit method need not be threadsafe. The +** xShutdown method is only called from [sqlite3_shutdown()] so it does +** not need to be threadsafe either. For all other methods, SQLite +** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the +** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which +** it is by default) and so the methods are automatically serialized. +** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other +** methods must be threadsafe or else make their own arrangements for +** serialization. +** +** SQLite will never invoke xInit() more than once without an intervening +** call to xShutdown(). +*/ +typedef struct sqlite3_mem_methods sqlite3_mem_methods; +struct sqlite3_mem_methods { + void *(*xMalloc)(int); /* Memory allocation function */ + void (*xFree)(void*); /* Free a prior allocation */ + void *(*xRealloc)(void*,int); /* Resize an allocation */ + int (*xSize)(void*); /* Return the size of an allocation */ + int (*xRoundup)(int); /* Round up request size to allocation size */ + int (*xInit)(void*); /* Initialize the memory allocator */ + void (*xShutdown)(void*); /* Deinitialize the memory allocator */ + void *pAppData; /* Argument to xInit() and xShutdown() */ +}; + +/* +** CAPI3REF: Configuration Options +** KEYWORDS: {configuration option} +** +** These constants are the available integer configuration options that +** can be passed as the first argument to the [sqlite3_config()] interface. +** +** Most of the configuration options for sqlite3_config() +** will only work if invoked prior to [sqlite3_initialize()] or after +** [sqlite3_shutdown()]. The few exceptions to this rule are called +** "anytime configuration options". +** ^Calling [sqlite3_config()] with a first argument that is not an +** anytime configuration option in between calls to [sqlite3_initialize()] and +** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE. +** +** The set of anytime configuration options can change (by insertions +** and/or deletions) from one release of SQLite to the next. +** As of SQLite version 3.42.0, the complete set of anytime configuration +** options is: +**
    +**
  • SQLITE_CONFIG_LOG +**
  • SQLITE_CONFIG_PCACHE_HDRSZ +**
+** +** New configuration options may be added in future releases of SQLite. +** Existing configuration options might be discontinued. Applications +** should check the return code from [sqlite3_config()] to make sure that +** the call worked. The [sqlite3_config()] interface will return a +** non-zero [error code] if a discontinued or unsupported configuration option +** is invoked. +** +**
+** [[SQLITE_CONFIG_SINGLETHREAD]]
SQLITE_CONFIG_SINGLETHREAD
+**
There are no arguments to this option. ^This option sets the +** [threading mode] to Single-thread. In other words, it disables +** all mutexing and puts SQLite into a mode where it can only be used +** by a single thread. ^If SQLite is compiled with +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then +** it is not possible to change the [threading mode] from its default +** value of Single-thread and so [sqlite3_config()] will return +** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD +** configuration option.
+** +** [[SQLITE_CONFIG_MULTITHREAD]]
SQLITE_CONFIG_MULTITHREAD
+**
There are no arguments to this option. ^This option sets the +** [threading mode] to Multi-thread. In other words, it disables +** mutexing on [database connection] and [prepared statement] objects. +** The application is responsible for serializing access to +** [database connections] and [prepared statements]. But other mutexes +** are enabled so that SQLite will be safe to use in a multi-threaded +** environment as long as no two threads attempt to use the same +** [database connection] at the same time. ^If SQLite is compiled with +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then +** it is not possible to set the Multi-thread [threading mode] and +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the +** SQLITE_CONFIG_MULTITHREAD configuration option.
+** +** [[SQLITE_CONFIG_SERIALIZED]]
SQLITE_CONFIG_SERIALIZED
+**
There are no arguments to this option. ^This option sets the +** [threading mode] to Serialized. In other words, this option enables +** all mutexes including the recursive +** mutexes on [database connection] and [prepared statement] objects. +** In this mode (which is the default when SQLite is compiled with +** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access +** to [database connections] and [prepared statements] so that the +** application is free to use the same [database connection] or the +** same [prepared statement] in different threads at the same time. +** ^If SQLite is compiled with +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then +** it is not possible to set the Serialized [threading mode] and +** [sqlite3_config()] will return [SQLITE_ERROR] if called with the +** SQLITE_CONFIG_SERIALIZED configuration option.
+** +** [[SQLITE_CONFIG_MALLOC]]
SQLITE_CONFIG_MALLOC
+**
^(The SQLITE_CONFIG_MALLOC option takes a single argument which is +** a pointer to an instance of the [sqlite3_mem_methods] structure. +** The argument specifies +** alternative low-level memory allocation routines to be used in place of +** the memory allocation routines built into SQLite.)^ ^SQLite makes +** its own private copy of the content of the [sqlite3_mem_methods] structure +** before the [sqlite3_config()] call returns.
+** +** [[SQLITE_CONFIG_GETMALLOC]]
SQLITE_CONFIG_GETMALLOC
+**
^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which +** is a pointer to an instance of the [sqlite3_mem_methods] structure. +** The [sqlite3_mem_methods] +** structure is filled with the currently defined memory allocation routines.)^ +** This option can be used to overload the default memory allocation +** routines with a wrapper that simulations memory allocation failure or +** tracks memory usage, for example.
+** +** [[SQLITE_CONFIG_SMALL_MALLOC]]
SQLITE_CONFIG_SMALL_MALLOC
+**
^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of +** type int, interpreted as a boolean, which if true provides a hint to +** SQLite that it should avoid large memory allocations if possible. +** SQLite will run faster if it is free to make large memory allocations, +** but some application might prefer to run slower in exchange for +** guarantees about memory fragmentation that are possible if large +** allocations are avoided. This hint is normally off. +**
+** +** [[SQLITE_CONFIG_MEMSTATUS]]
SQLITE_CONFIG_MEMSTATUS
+**
^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, +** interpreted as a boolean, which enables or disables the collection of +** memory allocation statistics. ^(When memory allocation statistics are +** disabled, the following SQLite interfaces become non-operational: +**
    +**
  • [sqlite3_hard_heap_limit64()] +**
  • [sqlite3_memory_used()] +**
  • [sqlite3_memory_highwater()] +**
  • [sqlite3_soft_heap_limit64()] +**
  • [sqlite3_status64()] +**
)^ +** ^Memory allocation statistics are enabled by default unless SQLite is +** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory +** allocation statistics are disabled by default. +**
+** +** [[SQLITE_CONFIG_SCRATCH]]
SQLITE_CONFIG_SCRATCH
+**
The SQLITE_CONFIG_SCRATCH option is no longer used. +**
+** +** [[SQLITE_CONFIG_PAGECACHE]]
SQLITE_CONFIG_PAGECACHE
+**
^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool +** that SQLite can use for the database page cache with the default page +** cache implementation. +** This configuration option is a no-op if an application-defined page +** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. +** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to +** 8-byte aligned memory (pMem), the size of each page cache line (sz), +** and the number of cache lines (N). +** The sz argument should be the size of the largest database page +** (a power of two between 512 and 65536) plus some extra bytes for each +** page header. ^The number of extra bytes needed by the page header +** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. +** ^It is harmless, apart from the wasted memory, +** for the sz parameter to be larger than necessary. The pMem +** argument must be either a NULL pointer or a pointer to an 8-byte +** aligned block of memory of at least sz*N bytes, otherwise +** subsequent behavior is undefined. +** ^When pMem is not NULL, SQLite will strive to use the memory provided +** to satisfy page cache needs, falling back to [sqlite3_malloc()] if +** a page cache line is larger than sz bytes or if all of the pMem buffer +** is exhausted. +** ^If pMem is NULL and N is non-zero, then each database connection +** does an initial bulk allocation for page cache memory +** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or +** of -1024*N bytes if N is negative, . ^If additional +** page cache memory is needed beyond what is provided by the initial +** allocation, then SQLite goes to [sqlite3_malloc()] separately for each +** additional cache line.
+** +** [[SQLITE_CONFIG_HEAP]]
SQLITE_CONFIG_HEAP
+**
^The SQLITE_CONFIG_HEAP option specifies a static memory buffer +** that SQLite will use for all of its dynamic memory allocation needs +** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. +** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled +** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns +** [SQLITE_ERROR] if invoked otherwise. +** ^There are three arguments to SQLITE_CONFIG_HEAP: +** An 8-byte aligned pointer to the memory, +** the number of bytes in the memory buffer, and the minimum allocation size. +** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts +** to using its default memory allocator (the system malloc() implementation), +** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the +** memory pointer is not NULL then the alternative memory +** allocator is engaged to handle all of SQLites memory allocation needs. +** The first pointer (the memory pointer) must be aligned to an 8-byte +** boundary or subsequent behavior of SQLite will be undefined. +** The minimum allocation size is capped at 2**12. Reasonable values +** for the minimum allocation size are 2**5 through 2**8.
+** +** [[SQLITE_CONFIG_MUTEX]]
SQLITE_CONFIG_MUTEX
+**
^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a +** pointer to an instance of the [sqlite3_mutex_methods] structure. +** The argument specifies alternative low-level mutex routines to be used +** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of +** the content of the [sqlite3_mutex_methods] structure before the call to +** [sqlite3_config()] returns. ^If SQLite is compiled with +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then +** the entire mutexing subsystem is omitted from the build and hence calls to +** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will +** return [SQLITE_ERROR].
+** +** [[SQLITE_CONFIG_GETMUTEX]]
SQLITE_CONFIG_GETMUTEX
+**
^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which +** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The +** [sqlite3_mutex_methods] +** structure is filled with the currently defined mutex routines.)^ +** This option can be used to overload the default mutex allocation +** routines with a wrapper used to track mutex usage for performance +** profiling or testing, for example. ^If SQLite is compiled with +** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then +** the entire mutexing subsystem is omitted from the build and hence calls to +** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will +** return [SQLITE_ERROR].
+** +** [[SQLITE_CONFIG_LOOKASIDE]]
SQLITE_CONFIG_LOOKASIDE
+**
^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine +** the default size of lookaside memory on each [database connection]. +** The first argument is the +** size of each lookaside buffer slot and the second is the number of +** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE +** sets the default lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] +** option to [sqlite3_db_config()] can be used to change the lookaside +** configuration on individual connections.)^
+** +** [[SQLITE_CONFIG_PCACHE2]]
SQLITE_CONFIG_PCACHE2
+**
^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is +** a pointer to an [sqlite3_pcache_methods2] object. This object specifies +** the interface to a custom page cache implementation.)^ +** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.
+** +** [[SQLITE_CONFIG_GETPCACHE2]]
SQLITE_CONFIG_GETPCACHE2
+**
^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which +** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of +** the current page cache implementation into that object.)^
+** +** [[SQLITE_CONFIG_LOG]]
SQLITE_CONFIG_LOG
+**
The SQLITE_CONFIG_LOG option is used to configure the SQLite +** global [error log]. +** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a +** function with a call signature of void(*)(void*,int,const char*), +** and a pointer to void. ^If the function pointer is not NULL, it is +** invoked by [sqlite3_log()] to process each logging event. ^If the +** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. +** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is +** passed through as the first parameter to the application-defined logger +** function whenever that function is invoked. ^The second parameter to +** the logger function is a copy of the first parameter to the corresponding +** [sqlite3_log()] call and is intended to be a [result code] or an +** [extended result code]. ^The third parameter passed to the logger is +** log message after formatting via [sqlite3_snprintf()]. +** The SQLite logging interface is not reentrant; the logger function +** supplied by the application must not invoke any SQLite interface. +** In a multi-threaded application, the application-defined logger +** function must be threadsafe.
+** +** [[SQLITE_CONFIG_URI]]
SQLITE_CONFIG_URI +**
^(The SQLITE_CONFIG_URI option takes a single argument of type int. +** If non-zero, then URI handling is globally enabled. If the parameter is zero, +** then URI handling is globally disabled.)^ ^If URI handling is globally +** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], +** [sqlite3_open16()] or +** specified as part of [ATTACH] commands are interpreted as URIs, regardless +** of whether or not the [SQLITE_OPEN_URI] flag is set when the database +** connection is opened. ^If it is globally disabled, filenames are +** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the +** database connection is opened. ^(By default, URI handling is globally +** disabled. The default value may be changed by compiling with the +** [SQLITE_USE_URI] symbol defined.)^ +** +** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]]
SQLITE_CONFIG_COVERING_INDEX_SCAN +**
^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer +** argument which is interpreted as a boolean in order to enable or disable +** the use of covering indices for full table scans in the query optimizer. +** ^The default setting is determined +** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" +** if that compile-time option is omitted. +** The ability to disable the use of covering indices for full table scans +** is because some incorrectly coded legacy applications might malfunction +** when the optimization is enabled. Providing the ability to +** disable the optimization allows the older, buggy application code to work +** without change even with newer versions of SQLite. +** +** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] +**
SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE +**
These options are obsolete and should not be used by new code. +** They are retained for backwards compatibility but are now no-ops. +**
+** +** [[SQLITE_CONFIG_SQLLOG]] +**
SQLITE_CONFIG_SQLLOG +**
This option is only available if sqlite is compiled with the +** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should +** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). +** The second should be of type (void*). The callback is invoked by the library +** in three separate circumstances, identified by the value passed as the +** fourth parameter. If the fourth parameter is 0, then the database connection +** passed as the second argument has just been opened. The third argument +** points to a buffer containing the name of the main database file. If the +** fourth parameter is 1, then the SQL statement that the third parameter +** points to has just been executed. Or, if the fourth parameter is 2, then +** the connection being passed as the second parameter is being closed. The +** third parameter is passed NULL In this case. An example of using this +** configuration option can be seen in the "test_sqllog.c" source file in +** the canonical SQLite source tree.
+** +** [[SQLITE_CONFIG_MMAP_SIZE]] +**
SQLITE_CONFIG_MMAP_SIZE +**
^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values +** that are the default mmap size limit (the default setting for +** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. +** ^The default setting can be overridden by each database connection using +** either the [PRAGMA mmap_size] command, or by using the +** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size +** will be silently truncated if necessary so that it does not exceed the +** compile-time maximum mmap size set by the +** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ +** ^If either argument to this option is negative, then that argument is +** changed to its compile-time default. +** +** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] +**
SQLITE_CONFIG_WIN32_HEAPSIZE +**
^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is +** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro +** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value +** that specifies the maximum size of the created heap. +** +** [[SQLITE_CONFIG_PCACHE_HDRSZ]] +**
SQLITE_CONFIG_PCACHE_HDRSZ +**
^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which +** is a pointer to an integer and writes into that integer the number of extra +** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. +** The amount of extra space required can change depending on the compiler, +** target platform, and SQLite version. +** +** [[SQLITE_CONFIG_PMASZ]] +**
SQLITE_CONFIG_PMASZ +**
^The SQLITE_CONFIG_PMASZ option takes a single parameter which +** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded +** sorter to that integer. The default minimum PMA Size is set by the +** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched +** to help with sort operations when multithreaded sorting +** is enabled (using the [PRAGMA threads] command) and the amount of content +** to be sorted exceeds the page size times the minimum of the +** [PRAGMA cache_size] setting and this value. +** +** [[SQLITE_CONFIG_STMTJRNL_SPILL]] +**
SQLITE_CONFIG_STMTJRNL_SPILL +**
^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which +** becomes the [statement journal] spill-to-disk threshold. +** [Statement journals] are held in memory until their size (in bytes) +** exceeds this threshold, at which point they are written to disk. +** Or if the threshold is -1, statement journals are always held +** exclusively in memory. +** Since many statement journals never become large, setting the spill +** threshold to a value such as 64KiB can greatly reduce the amount of +** I/O required to support statement rollback. +** The default value for this setting is controlled by the +** [SQLITE_STMTJRNL_SPILL] compile-time option. +** +** [[SQLITE_CONFIG_SORTERREF_SIZE]] +**
SQLITE_CONFIG_SORTERREF_SIZE +**
The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter +** of type (int) - the new value of the sorter-reference size threshold. +** Usually, when SQLite uses an external sort to order records according +** to an ORDER BY clause, all fields required by the caller are present in the +** sorted records. However, if SQLite determines based on the declared type +** of a table column that its values are likely to be very large - larger +** than the configured sorter-reference size threshold - then a reference +** is stored in each sorted record and the required column values loaded +** from the database as records are returned in sorted order. The default +** value for this option is to never use this optimization. Specifying a +** negative value for this option restores the default behavior. +** This option is only available if SQLite is compiled with the +** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. +** +** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] +**
SQLITE_CONFIG_MEMDB_MAXSIZE +**
The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter +** [sqlite3_int64] parameter which is the default maximum size for an in-memory +** database created using [sqlite3_deserialize()]. This default maximum +** size can be adjusted up or down for individual databases using the +** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this +** configuration setting is never used, then the default maximum is determined +** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that +** compile-time option is not set, then the default maximum is 1073741824. +** +** [[SQLITE_CONFIG_ROWID_IN_VIEW]] +**
SQLITE_CONFIG_ROWID_IN_VIEW +**
The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability +** for VIEWs to have a ROWID. The capability can only be enabled if SQLite is +** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability +** defaults to on. This configuration option queries the current setting or +** changes the setting to off or on. The argument is a pointer to an integer. +** If that integer initially holds a value of 1, then the ability for VIEWs to +** have ROWIDs is activated. If the integer initially holds zero, then the +** ability is deactivated. Any other initial value for the integer leaves the +** setting unchanged. After changes, if any, the integer is written with +** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off. If SQLite +** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and +** recommended case) then the integer is always filled with zero, regardless +** if its initial value. +**
+*/ +#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ +#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ +#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ +#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ +#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ +#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ +#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ +#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ +#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ +#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ +#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ +/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ +#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ +#define SQLITE_CONFIG_PCACHE 14 /* no-op */ +#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ +#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ +#define SQLITE_CONFIG_URI 17 /* int */ +#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ +#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ +#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ +#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ +#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ +#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ +#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ +#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ +#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ +#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ +#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ +#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ +#define SQLITE_CONFIG_ROWID_IN_VIEW 30 /* int* */ + +/* +** CAPI3REF: Database Connection Configuration Options +** +** These constants are the available integer configuration options that +** can be passed as the second argument to the [sqlite3_db_config()] interface. +** +** New configuration options may be added in future releases of SQLite. +** Existing configuration options might be discontinued. Applications +** should check the return code from [sqlite3_db_config()] to make sure that +** the call worked. ^The [sqlite3_db_config()] interface will return a +** non-zero [error code] if a discontinued or unsupported configuration option +** is invoked. +** +**
+** [[SQLITE_DBCONFIG_LOOKASIDE]] +**
SQLITE_DBCONFIG_LOOKASIDE
+**
^This option takes three additional arguments that determine the +** [lookaside memory allocator] configuration for the [database connection]. +** ^The first argument (the third parameter to [sqlite3_db_config()] is a +** pointer to a memory buffer to use for lookaside memory. +** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb +** may be NULL in which case SQLite will allocate the +** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the +** size of each lookaside buffer slot. ^The third argument is the number of +** slots. The size of the buffer in the first argument must be greater than +** or equal to the product of the second and third arguments. The buffer +** must be aligned to an 8-byte boundary. ^If the second argument to +** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally +** rounded down to the next smaller multiple of 8. ^(The lookaside memory +** configuration for a database connection can only be changed when that +** connection is not currently using lookaside memory, or in other words +** when the "current value" returned by +** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero. +** Any attempt to change the lookaside memory configuration when lookaside +** memory is in use leaves the configuration unchanged and returns +** [SQLITE_BUSY].)^
+** +** [[SQLITE_DBCONFIG_ENABLE_FKEY]] +**
SQLITE_DBCONFIG_ENABLE_FKEY
+**
^This option is used to enable or disable the enforcement of +** [foreign key constraints]. There should be two additional arguments. +** The first argument is an integer which is 0 to disable FK enforcement, +** positive to enable FK enforcement or negative to leave FK enforcement +** unchanged. The second parameter is a pointer to an integer into which +** is written 0 or 1 to indicate whether FK enforcement is off or on +** following this call. The second parameter may be a NULL pointer, in +** which case the FK enforcement setting is not reported back.
+** +** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] +**
SQLITE_DBCONFIG_ENABLE_TRIGGER
+**
^This option is used to enable or disable [CREATE TRIGGER | triggers]. +** There should be two additional arguments. +** The first argument is an integer which is 0 to disable triggers, +** positive to enable triggers or negative to leave the setting unchanged. +** The second parameter is a pointer to an integer into which +** is written 0 or 1 to indicate whether triggers are disabled or enabled +** following this call. The second parameter may be a NULL pointer, in +** which case the trigger setting is not reported back. +** +**

Originally this option disabled all triggers. ^(However, since +** SQLite version 3.35.0, TEMP triggers are still allowed even if +** this option is off. So, in other words, this option now only disables +** triggers in the main database schema or in the schemas of ATTACH-ed +** databases.)^

+** +** [[SQLITE_DBCONFIG_ENABLE_VIEW]] +**
SQLITE_DBCONFIG_ENABLE_VIEW
+**
^This option is used to enable or disable [CREATE VIEW | views]. +** There should be two additional arguments. +** The first argument is an integer which is 0 to disable views, +** positive to enable views or negative to leave the setting unchanged. +** The second parameter is a pointer to an integer into which +** is written 0 or 1 to indicate whether views are disabled or enabled +** following this call. The second parameter may be a NULL pointer, in +** which case the view setting is not reported back. +** +**

Originally this option disabled all views. ^(However, since +** SQLite version 3.35.0, TEMP views are still allowed even if +** this option is off. So, in other words, this option now only disables +** views in the main database schema or in the schemas of ATTACH-ed +** databases.)^

+** +** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] +**
SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER
+**
^This option is used to enable or disable the +** [fts3_tokenizer()] function which is part of the +** [FTS3] full-text search engine extension. +** There should be two additional arguments. +** The first argument is an integer which is 0 to disable fts3_tokenizer() or +** positive to enable fts3_tokenizer() or negative to leave the setting +** unchanged. +** The second parameter is a pointer to an integer into which +** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled +** following this call. The second parameter may be a NULL pointer, in +** which case the new setting is not reported back.
+** +** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] +**
SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION
+**
^This option is used to enable or disable the [sqlite3_load_extension()] +** interface independently of the [load_extension()] SQL function. +** The [sqlite3_enable_load_extension()] API enables or disables both the +** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. +** There should be two additional arguments. +** When the first argument to this interface is 1, then only the C-API is +** enabled and the SQL function remains disabled. If the first argument to +** this interface is 0, then both the C-API and the SQL function are disabled. +** If the first argument is -1, then no changes are made to state of either the +** C-API or the SQL function. +** The second parameter is a pointer to an integer into which +** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface +** is disabled or enabled following this call. The second parameter may +** be a NULL pointer, in which case the new setting is not reported back. +**
+** +** [[SQLITE_DBCONFIG_MAINDBNAME]]
SQLITE_DBCONFIG_MAINDBNAME
+**
^This option is used to change the name of the "main" database +** schema. ^The sole argument is a pointer to a constant UTF8 string +** which will become the new schema name in place of "main". ^SQLite +** does not make a copy of the new main schema name string, so the application +** must ensure that the argument passed into this DBCONFIG option is unchanged +** until after the database connection closes. +**
+** +** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] +**
SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE
+**
Usually, when a database in wal mode is closed or detached from a +** database handle, SQLite checks if this will mean that there are now no +** connections at all to the database. If so, it performs a checkpoint +** operation before closing the connection. This option may be used to +** override this behavior. The first parameter passed to this operation +** is an integer - positive to disable checkpoints-on-close, or zero (the +** default) to enable them, and negative to leave the setting unchanged. +** The second parameter is a pointer to an integer +** into which is written 0 or 1 to indicate whether checkpoints-on-close +** have been disabled - 0 if they are not disabled, 1 if they are. +**
+** +** [[SQLITE_DBCONFIG_ENABLE_QPSG]]
SQLITE_DBCONFIG_ENABLE_QPSG
+**
^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates +** the [query planner stability guarantee] (QPSG). When the QPSG is active, +** a single SQL query statement will always use the same algorithm regardless +** of values of [bound parameters].)^ The QPSG disables some query optimizations +** that look at the values of bound parameters, which can make some queries +** slower. But the QPSG has the advantage of more predictable behavior. With +** the QPSG active, SQLite will always use the same query plan in the field as +** was used during testing in the lab. +** The first argument to this setting is an integer which is 0 to disable +** the QPSG, positive to enable QPSG, or negative to leave the setting +** unchanged. The second parameter is a pointer to an integer into which +** is written 0 or 1 to indicate whether the QPSG is disabled or enabled +** following this call. +**
+** +** [[SQLITE_DBCONFIG_TRIGGER_EQP]]
SQLITE_DBCONFIG_TRIGGER_EQP
+**
By default, the output of EXPLAIN QUERY PLAN commands does not +** include output for any operations performed by trigger programs. This +** option is used to set or clear (the default) a flag that governs this +** behavior. The first parameter passed to this operation is an integer - +** positive to enable output for trigger programs, or zero to disable it, +** or negative to leave the setting unchanged. +** The second parameter is a pointer to an integer into which is written +** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if +** it is not disabled, 1 if it is. +**
+** +** [[SQLITE_DBCONFIG_RESET_DATABASE]]
SQLITE_DBCONFIG_RESET_DATABASE
+**
Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run +** [VACUUM] in order to reset a database back to an empty database +** with no schema and no content. The following process works even for +** a badly corrupted database file: +**
    +**
  1. If the database connection is newly opened, make sure it has read the +** database schema by preparing then discarding some query against the +** database, or calling sqlite3_table_column_metadata(), ignoring any +** errors. This step is only necessary if the application desires to keep +** the database in WAL mode after the reset if it was in WAL mode before +** the reset. +**
  2. sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); +**
  3. [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); +**
  4. sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); +**
+** Because resetting a database is destructive and irreversible, the +** process requires the use of this obscure API and multiple steps to +** help ensure that it does not happen by accident. Because this +** feature must be capable of resetting corrupt databases, and +** shutting down virtual tables may require access to that corrupt +** storage, the library must abandon any installed virtual tables +** without calling their xDestroy() methods. +** +** [[SQLITE_DBCONFIG_DEFENSIVE]]
SQLITE_DBCONFIG_DEFENSIVE
+**
The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the +** "defensive" flag for a database connection. When the defensive +** flag is enabled, language features that allow ordinary SQL to +** deliberately corrupt the database file are disabled. The disabled +** features include but are not limited to the following: +**
    +**
  • The [PRAGMA writable_schema=ON] statement. +**
  • The [PRAGMA journal_mode=OFF] statement. +**
  • The [PRAGMA schema_version=N] statement. +**
  • Writes to the [sqlite_dbpage] virtual table. +**
  • Direct writes to [shadow tables]. +**
+**
+** +** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]]
SQLITE_DBCONFIG_WRITABLE_SCHEMA
+**
The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the +** "writable_schema" flag. This has the same effect and is logically equivalent +** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. +** The first argument to this setting is an integer which is 0 to disable +** the writable_schema, positive to enable writable_schema, or negative to +** leave the setting unchanged. The second parameter is a pointer to an +** integer into which is written 0 or 1 to indicate whether the writable_schema +** is enabled or disabled following this call. +**
+** +** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] +**
SQLITE_DBCONFIG_LEGACY_ALTER_TABLE
+**
The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates +** the legacy behavior of the [ALTER TABLE RENAME] command such it +** behaves as it did prior to [version 3.24.0] (2018-06-04). See the +** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for +** additional information. This feature can also be turned on and off +** using the [PRAGMA legacy_alter_table] statement. +**
+** +** [[SQLITE_DBCONFIG_DQS_DML]] +**
SQLITE_DBCONFIG_DQS_DML
+**
The SQLITE_DBCONFIG_DQS_DML option activates or deactivates +** the legacy [double-quoted string literal] misfeature for DML statements +** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The +** default value of this setting is determined by the [-DSQLITE_DQS] +** compile-time option. +**
+** +** [[SQLITE_DBCONFIG_DQS_DDL]] +**
SQLITE_DBCONFIG_DQS_DDL
+**
The SQLITE_DBCONFIG_DQS option activates or deactivates +** the legacy [double-quoted string literal] misfeature for DDL statements, +** such as CREATE TABLE and CREATE INDEX. The +** default value of this setting is determined by the [-DSQLITE_DQS] +** compile-time option. +**
+** +** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] +**
SQLITE_DBCONFIG_TRUSTED_SCHEMA
+**
The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to +** assume that database schemas are untainted by malicious content. +** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite +** takes additional defensive steps to protect the application from harm +** including: +**
    +**
  • Prohibit the use of SQL functions inside triggers, views, +** CHECK constraints, DEFAULT clauses, expression indexes, +** partial indexes, or generated columns +** unless those functions are tagged with [SQLITE_INNOCUOUS]. +**
  • Prohibit the use of virtual tables inside of triggers or views +** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. +**
+** This setting defaults to "on" for legacy compatibility, however +** all applications are advised to turn it off if possible. This setting +** can also be controlled using the [PRAGMA trusted_schema] statement. +**
+** +** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] +**
SQLITE_DBCONFIG_LEGACY_FILE_FORMAT
+**
The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates +** the legacy file format flag. When activated, this flag causes all newly +** created database file to have a schema format version number (the 4-byte +** integer found at offset 44 into the database header) of 1. This in turn +** means that the resulting database file will be readable and writable by +** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, +** newly created databases are generally not understandable by SQLite versions +** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there +** is now scarcely any need to generate database files that are compatible +** all the way back to version 3.0.0, and so this setting is of little +** practical use, but is provided so that SQLite can continue to claim the +** ability to generate new database files that are compatible with version +** 3.0.0. +**

Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, +** the [VACUUM] command will fail with an obscure error when attempting to +** process a table with generated columns and a descending index. This is +** not considered a bug since SQLite versions 3.3.0 and earlier do not support +** either generated columns or descending indexes. +**

+** +** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]] +**
SQLITE_DBCONFIG_STMT_SCANSTATUS
+**
The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in +** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears +** a flag that enables collection of the sqlite3_stmt_scanstatus_v2() +** statistics. For statistics to be collected, the flag must be set on +** the database handle both when the SQL statement is prepared and when it +** is stepped. The flag is set (collection of statistics is enabled) +** by default. This option takes two arguments: an integer and a pointer to +** an integer.. The first argument is 1, 0, or -1 to enable, disable, or +** leave unchanged the statement scanstatus option. If the second argument +** is not NULL, then the value of the statement scanstatus setting after +** processing the first argument is written into the integer that the second +** argument points to. +**
+** +** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]] +**
SQLITE_DBCONFIG_REVERSE_SCANORDER
+**
The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order +** in which tables and indexes are scanned so that the scans start at the end +** and work toward the beginning rather than starting at the beginning and +** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the +** same as setting [PRAGMA reverse_unordered_selects]. This option takes +** two arguments which are an integer and a pointer to an integer. The first +** argument is 1, 0, or -1 to enable, disable, or leave unchanged the +** reverse scan order flag, respectively. If the second argument is not NULL, +** then 0 or 1 is written into the integer that the second argument points to +** depending on if the reverse scan order flag is set after processing the +** first argument. +**
+** +**
+*/ +#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ +#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ +#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ +#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ +#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ +#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ +#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ +#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ +#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ +#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ +#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ +#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ +#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ +#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ +#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ +#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ +#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ +#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ +#define SQLITE_DBCONFIG_STMT_SCANSTATUS 1018 /* int int* */ +#define SQLITE_DBCONFIG_REVERSE_SCANORDER 1019 /* int int* */ +#define SQLITE_DBCONFIG_MAX 1019 /* Largest DBCONFIG */ + +/* +** CAPI3REF: Enable Or Disable Extended Result Codes +** METHOD: sqlite3 +** +** ^The sqlite3_extended_result_codes() routine enables or disables the +** [extended result codes] feature of SQLite. ^The extended result +** codes are disabled by default for historical compatibility. +*/ +SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); + +/* +** CAPI3REF: Last Insert Rowid +** METHOD: sqlite3 +** +** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) +** has a unique 64-bit signed +** integer key called the [ROWID | "rowid"]. ^The rowid is always available +** as an undeclared column named ROWID, OID, or _ROWID_ as long as those +** names are not also used by explicitly declared columns. ^If +** the table has a column of type [INTEGER PRIMARY KEY] then that column +** is another alias for the rowid. +** +** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of +** the most recent successful [INSERT] into a rowid table or [virtual table] +** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not +** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred +** on the database connection D, then sqlite3_last_insert_rowid(D) returns +** zero. +** +** As well as being set automatically as rows are inserted into database +** tables, the value returned by this function may be set explicitly by +** [sqlite3_set_last_insert_rowid()] +** +** Some virtual table implementations may INSERT rows into rowid tables as +** part of committing a transaction (e.g. to flush data accumulated in memory +** to disk). In this case subsequent calls to this function return the rowid +** associated with these internal INSERT operations, which leads to +** unintuitive results. Virtual table implementations that do write to rowid +** tables in this way can avoid this problem by restoring the original +** rowid value using [sqlite3_set_last_insert_rowid()] before returning +** control to the user. +** +** ^(If an [INSERT] occurs within a trigger then this routine will +** return the [rowid] of the inserted row as long as the trigger is +** running. Once the trigger program ends, the value returned +** by this routine reverts to what it was before the trigger was fired.)^ +** +** ^An [INSERT] that fails due to a constraint violation is not a +** successful [INSERT] and does not change the value returned by this +** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, +** and INSERT OR ABORT make no changes to the return value of this +** routine when their insertion fails. ^(When INSERT OR REPLACE +** encounters a constraint violation, it does not fail. The +** INSERT continues to completion after deleting rows that caused +** the constraint problem so INSERT OR REPLACE will always change +** the return value of this interface.)^ +** +** ^For the purposes of this routine, an [INSERT] is considered to +** be successful even if it is subsequently rolled back. +** +** This function is accessible to SQL statements via the +** [last_insert_rowid() SQL function]. +** +** If a separate thread performs a new [INSERT] on the same +** database connection while the [sqlite3_last_insert_rowid()] +** function is running and thus changes the last insert [rowid], +** then the value returned by [sqlite3_last_insert_rowid()] is +** unpredictable and might not equal either the old or the new +** last insert [rowid]. +*/ +SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); + +/* +** CAPI3REF: Set the Last Insert Rowid value. +** METHOD: sqlite3 +** +** The sqlite3_set_last_insert_rowid(D, R) method allows the application to +** set the value returned by calling sqlite3_last_insert_rowid(D) to R +** without inserting a row into the database. +*/ +SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); + +/* +** CAPI3REF: Count The Number Of Rows Modified +** METHOD: sqlite3 +** +** ^These functions return the number of rows modified, inserted or +** deleted by the most recently completed INSERT, UPDATE or DELETE +** statement on the database connection specified by the only parameter. +** The two functions are identical except for the type of the return value +** and that if the number of rows modified by the most recent INSERT, UPDATE +** or DELETE is greater than the maximum value supported by type "int", then +** the return value of sqlite3_changes() is undefined. ^Executing any other +** type of SQL statement does not modify the value returned by these functions. +** +** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are +** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], +** [foreign key actions] or [REPLACE] constraint resolution are not counted. +** +** Changes to a view that are intercepted by +** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value +** returned by sqlite3_changes() immediately after an INSERT, UPDATE or +** DELETE statement run on a view is always zero. Only changes made to real +** tables are counted. +** +** Things are more complicated if the sqlite3_changes() function is +** executed while a trigger program is running. This may happen if the +** program uses the [changes() SQL function], or if some other callback +** function invokes sqlite3_changes() directly. Essentially: +** +**
    +**
  • ^(Before entering a trigger program the value returned by +** sqlite3_changes() function is saved. After the trigger program +** has finished, the original value is restored.)^ +** +**
  • ^(Within a trigger program each INSERT, UPDATE and DELETE +** statement sets the value returned by sqlite3_changes() +** upon completion as normal. Of course, this value will not include +** any changes performed by sub-triggers, as the sqlite3_changes() +** value will be saved and restored after each sub-trigger has run.)^ +**
+** +** ^This means that if the changes() SQL function (or similar) is used +** by the first INSERT, UPDATE or DELETE statement within a trigger, it +** returns the value as set when the calling statement began executing. +** ^If it is used by the second or subsequent such statement within a trigger +** program, the value returned reflects the number of rows modified by the +** previous INSERT, UPDATE or DELETE statement within the same trigger. +** +** If a separate thread makes changes on the same database connection +** while [sqlite3_changes()] is running then the value returned +** is unpredictable and not meaningful. +** +** See also: +**
    +**
  • the [sqlite3_total_changes()] interface +**
  • the [count_changes pragma] +**
  • the [changes() SQL function] +**
  • the [data_version pragma] +**
+*/ +SQLITE_API int sqlite3_changes(sqlite3*); +SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*); + +/* +** CAPI3REF: Total Number Of Rows Modified +** METHOD: sqlite3 +** +** ^These functions return the total number of rows inserted, modified or +** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed +** since the database connection was opened, including those executed as +** part of trigger programs. The two functions are identical except for the +** type of the return value and that if the number of rows modified by the +** connection exceeds the maximum value supported by type "int", then +** the return value of sqlite3_total_changes() is undefined. ^Executing +** any other type of SQL statement does not affect the value returned by +** sqlite3_total_changes(). +** +** ^Changes made as part of [foreign key actions] are included in the +** count, but those made as part of REPLACE constraint resolution are +** not. ^Changes to a view that are intercepted by INSTEAD OF triggers +** are not counted. +** +** The [sqlite3_total_changes(D)] interface only reports the number +** of rows that changed due to SQL statement run against database +** connection D. Any changes by other database connections are ignored. +** To detect changes against a database file from other database +** connections use the [PRAGMA data_version] command or the +** [SQLITE_FCNTL_DATA_VERSION] [file control]. +** +** If a separate thread makes changes on the same database connection +** while [sqlite3_total_changes()] is running then the value +** returned is unpredictable and not meaningful. +** +** See also: +**
    +**
  • the [sqlite3_changes()] interface +**
  • the [count_changes pragma] +**
  • the [changes() SQL function] +**
  • the [data_version pragma] +**
  • the [SQLITE_FCNTL_DATA_VERSION] [file control] +**
+*/ +SQLITE_API int sqlite3_total_changes(sqlite3*); +SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*); + +/* +** CAPI3REF: Interrupt A Long-Running Query +** METHOD: sqlite3 +** +** ^This function causes any pending database operation to abort and +** return at its earliest opportunity. This routine is typically +** called in response to a user action such as pressing "Cancel" +** or Ctrl-C where the user wants a long query operation to halt +** immediately. +** +** ^It is safe to call this routine from a thread different from the +** thread that is currently running the database operation. But it +** is not safe to call this routine with a [database connection] that +** is closed or might close before sqlite3_interrupt() returns. +** +** ^If an SQL operation is very nearly finished at the time when +** sqlite3_interrupt() is called, then it might not have an opportunity +** to be interrupted and might continue to completion. +** +** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. +** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE +** that is inside an explicit transaction, then the entire transaction +** will be rolled back automatically. +** +** ^The sqlite3_interrupt(D) call is in effect until all currently running +** SQL statements on [database connection] D complete. ^Any new SQL statements +** that are started after the sqlite3_interrupt() call and before the +** running statement count reaches zero are interrupted as if they had been +** running prior to the sqlite3_interrupt() call. ^New SQL statements +** that are started after the running statement count reaches zero are +** not effected by the sqlite3_interrupt(). +** ^A call to sqlite3_interrupt(D) that occurs when there are no running +** SQL statements is a no-op and has no effect on SQL statements +** that are started after the sqlite3_interrupt() call returns. +** +** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether +** or not an interrupt is currently in effect for [database connection] D. +** It returns 1 if an interrupt is currently in effect, or 0 otherwise. +*/ +SQLITE_API void sqlite3_interrupt(sqlite3*); +SQLITE_API int sqlite3_is_interrupted(sqlite3*); + +/* +** CAPI3REF: Determine If An SQL Statement Is Complete +** +** These routines are useful during command-line input to determine if the +** currently entered text seems to form a complete SQL statement or +** if additional input is needed before sending the text into +** SQLite for parsing. ^These routines return 1 if the input string +** appears to be a complete SQL statement. ^A statement is judged to be +** complete if it ends with a semicolon token and is not a prefix of a +** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within +** string literals or quoted identifier names or comments are not +** independent tokens (they are part of the token in which they are +** embedded) and thus do not count as a statement terminator. ^Whitespace +** and comments that follow the final semicolon are ignored. +** +** ^These routines return 0 if the statement is incomplete. ^If a +** memory allocation fails, then SQLITE_NOMEM is returned. +** +** ^These routines do not parse the SQL statements thus +** will not detect syntactically incorrect SQL. +** +** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior +** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked +** automatically by sqlite3_complete16(). If that initialization fails, +** then the return value from sqlite3_complete16() will be non-zero +** regardless of whether or not the input SQL is complete.)^ +** +** The input to [sqlite3_complete()] must be a zero-terminated +** UTF-8 string. +** +** The input to [sqlite3_complete16()] must be a zero-terminated +** UTF-16 string in native byte order. +*/ +SQLITE_API int sqlite3_complete(const char *sql); +SQLITE_API int sqlite3_complete16(const void *sql); + +/* +** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors +** KEYWORDS: {busy-handler callback} {busy handler} +** METHOD: sqlite3 +** +** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X +** that might be invoked with argument P whenever +** an attempt is made to access a database table associated with +** [database connection] D when another thread +** or process has the table locked. +** The sqlite3_busy_handler() interface is used to implement +** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. +** +** ^If the busy callback is NULL, then [SQLITE_BUSY] +** is returned immediately upon encountering the lock. ^If the busy callback +** is not NULL, then the callback might be invoked with two arguments. +** +** ^The first argument to the busy handler is a copy of the void* pointer which +** is the third argument to sqlite3_busy_handler(). ^The second argument to +** the busy handler callback is the number of times that the busy handler has +** been invoked previously for the same locking event. ^If the +** busy callback returns 0, then no additional attempts are made to +** access the database and [SQLITE_BUSY] is returned +** to the application. +** ^If the callback returns non-zero, then another attempt +** is made to access the database and the cycle repeats. +** +** The presence of a busy handler does not guarantee that it will be invoked +** when there is lock contention. ^If SQLite determines that invoking the busy +** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] +** to the application instead of invoking the +** busy handler. +** Consider a scenario where one process is holding a read lock that +** it is trying to promote to a reserved lock and +** a second process is holding a reserved lock that it is trying +** to promote to an exclusive lock. The first process cannot proceed +** because it is blocked by the second and the second process cannot +** proceed because it is blocked by the first. If both processes +** invoke the busy handlers, neither will make any progress. Therefore, +** SQLite returns [SQLITE_BUSY] for the first process, hoping that this +** will induce the first process to release its read lock and allow +** the second process to proceed. +** +** ^The default busy callback is NULL. +** +** ^(There can only be a single busy handler defined for each +** [database connection]. Setting a new busy handler clears any +** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] +** or evaluating [PRAGMA busy_timeout=N] will change the +** busy handler and thus clear any previously set busy handler. +** +** The busy callback should not take any actions which modify the +** database connection that invoked the busy handler. In other words, +** the busy handler is not reentrant. Any such actions +** result in undefined behavior. +** +** A busy handler must not close the database connection +** or [prepared statement] that invoked the busy handler. +*/ +SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); + +/* +** CAPI3REF: Set A Busy Timeout +** METHOD: sqlite3 +** +** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps +** for a specified amount of time when a table is locked. ^The handler +** will sleep multiple times until at least "ms" milliseconds of sleeping +** have accumulated. ^After at least "ms" milliseconds of sleeping, +** the handler returns 0 which causes [sqlite3_step()] to return +** [SQLITE_BUSY]. +** +** ^Calling this routine with an argument less than or equal to zero +** turns off all busy handlers. +** +** ^(There can only be a single busy handler for a particular +** [database connection] at any given moment. If another busy handler +** was defined (using [sqlite3_busy_handler()]) prior to calling +** this routine, that other busy handler is cleared.)^ +** +** See also: [PRAGMA busy_timeout] +*/ +SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); + +/* +** CAPI3REF: Convenience Routines For Running Queries +** METHOD: sqlite3 +** +** This is a legacy interface that is preserved for backwards compatibility. +** Use of this interface is not recommended. +** +** Definition: A result table is memory data structure created by the +** [sqlite3_get_table()] interface. A result table records the +** complete query results from one or more queries. +** +** The table conceptually has a number of rows and columns. But +** these numbers are not part of the result table itself. These +** numbers are obtained separately. Let N be the number of rows +** and M be the number of columns. +** +** A result table is an array of pointers to zero-terminated UTF-8 strings. +** There are (N+1)*M elements in the array. The first M pointers point +** to zero-terminated strings that contain the names of the columns. +** The remaining entries all point to query results. NULL values result +** in NULL pointers. All other values are in their UTF-8 zero-terminated +** string representation as returned by [sqlite3_column_text()]. +** +** A result table might consist of one or more memory allocations. +** It is not safe to pass a result table directly to [sqlite3_free()]. +** A result table should be deallocated using [sqlite3_free_table()]. +** +** ^(As an example of the result table format, suppose a query result +** is as follows: +** +** 
+**        Name        | Age
+**        -----------------------
+**        Alice       | 43
+**        Bob         | 28
+**        Cindy       | 21
+**
+** +** There are two columns (M==2) and three rows (N==3). Thus the +** result table has 8 entries. Suppose the result table is stored +** in an array named azResult. Then azResult holds this content: +** +** 
+**        azResult[0] = "Name";
+**        azResult[1] = "Age";
+**        azResult[2] = "Alice";
+**        azResult[3] = "43";
+**        azResult[4] = "Bob";
+**        azResult[5] = "28";
+**        azResult[6] = "Cindy";
+**        azResult[7] = "21";
+**
)^ +** +** ^The sqlite3_get_table() function evaluates one or more +** semicolon-separated SQL statements in the zero-terminated UTF-8 +** string of its 2nd parameter and returns a result table to the +** pointer given in its 3rd parameter. +** +** After the application has finished with the result from sqlite3_get_table(), +** it must pass the result table pointer to sqlite3_free_table() in order to +** release the memory that was malloced. Because of the way the +** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling +** function must not try to call [sqlite3_free()] directly. Only +** [sqlite3_free_table()] is able to release the memory properly and safely. +** +** The sqlite3_get_table() interface is implemented as a wrapper around +** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access +** to any internal data structures of SQLite. It uses only the public +** interface defined here. As a consequence, errors that occur in the +** wrapper layer outside of the internal [sqlite3_exec()] call are not +** reflected in subsequent calls to [sqlite3_errcode()] or +** [sqlite3_errmsg()]. +*/ +SQLITE_API int sqlite3_get_table( + sqlite3 *db, /* An open database */ + const char *zSql, /* SQL to be evaluated */ + char ***pazResult, /* Results of the query */ + int *pnRow, /* Number of result rows written here */ + int *pnColumn, /* Number of result columns written here */ + char **pzErrmsg /* Error msg written here */ +); +SQLITE_API void sqlite3_free_table(char **result); + +/* +** CAPI3REF: Formatted String Printing Functions +** +** These routines are work-alikes of the "printf()" family of functions +** from the standard C library. +** These routines understand most of the common formatting options from +** the standard library printf() +** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). +** See the [built-in printf()] documentation for details. +** +** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their +** results into memory obtained from [sqlite3_malloc64()]. +** The strings returned by these two routines should be +** released by [sqlite3_free()]. ^Both routines return a +** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough +** memory to hold the resulting string. +** +** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from +** the standard C library. The result is written into the +** buffer supplied as the second parameter whose size is given by +** the first parameter. Note that the order of the +** first two parameters is reversed from snprintf().)^ This is an +** historical accident that cannot be fixed without breaking +** backwards compatibility. ^(Note also that sqlite3_snprintf() +** returns a pointer to its buffer instead of the number of +** characters actually written into the buffer.)^ We admit that +** the number of characters written would be a more useful return +** value but we cannot change the implementation of sqlite3_snprintf() +** now without breaking compatibility. +** +** ^As long as the buffer size is greater than zero, sqlite3_snprintf() +** guarantees that the buffer is always zero-terminated. ^The first +** parameter "n" is the total size of the buffer, including space for +** the zero terminator. So the longest string that can be completely +** written will be n-1 characters. +** +** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). +** +** See also: [built-in printf()], [printf() SQL function] +*/ +SQLITE_API char *sqlite3_mprintf(const char*,...); +SQLITE_API char *sqlite3_vmprintf(const char*, va_list); +SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); +SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); + +/* +** CAPI3REF: Memory Allocation Subsystem +** +** The SQLite core uses these three routines for all of its own +** internal memory allocation needs. "Core" in the previous sentence +** does not include operating-system specific [VFS] implementation. The +** Windows VFS uses native malloc() and free() for some operations. +** +** ^The sqlite3_malloc() routine returns a pointer to a block +** of memory at least N bytes in length, where N is the parameter. +** ^If sqlite3_malloc() is unable to obtain sufficient free +** memory, it returns a NULL pointer. ^If the parameter N to +** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns +** a NULL pointer. +** +** ^The sqlite3_malloc64(N) routine works just like +** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead +** of a signed 32-bit integer. +** +** ^Calling sqlite3_free() with a pointer previously returned +** by sqlite3_malloc() or sqlite3_realloc() releases that memory so +** that it might be reused. ^The sqlite3_free() routine is +** a no-op if is called with a NULL pointer. Passing a NULL pointer +** to sqlite3_free() is harmless. After being freed, memory +** should neither be read nor written. Even reading previously freed +** memory might result in a segmentation fault or other severe error. +** Memory corruption, a segmentation fault, or other severe error +** might result if sqlite3_free() is called with a non-NULL pointer that +** was not obtained from sqlite3_malloc() or sqlite3_realloc(). +** +** ^The sqlite3_realloc(X,N) interface attempts to resize a +** prior memory allocation X to be at least N bytes. +** ^If the X parameter to sqlite3_realloc(X,N) +** is a NULL pointer then its behavior is identical to calling +** sqlite3_malloc(N). +** ^If the N parameter to sqlite3_realloc(X,N) is zero or +** negative then the behavior is exactly the same as calling +** sqlite3_free(X). +** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation +** of at least N bytes in size or NULL if insufficient memory is available. +** ^If M is the size of the prior allocation, then min(N,M) bytes +** of the prior allocation are copied into the beginning of buffer returned +** by sqlite3_realloc(X,N) and the prior allocation is freed. +** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the +** prior allocation is not freed. +** +** ^The sqlite3_realloc64(X,N) interfaces works the same as +** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead +** of a 32-bit signed integer. +** +** ^If X is a memory allocation previously obtained from sqlite3_malloc(), +** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then +** sqlite3_msize(X) returns the size of that memory allocation in bytes. +** ^The value returned by sqlite3_msize(X) might be larger than the number +** of bytes requested when X was allocated. ^If X is a NULL pointer then +** sqlite3_msize(X) returns zero. If X points to something that is not +** the beginning of memory allocation, or if it points to a formerly +** valid memory allocation that has now been freed, then the behavior +** of sqlite3_msize(X) is undefined and possibly harmful. +** +** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), +** sqlite3_malloc64(), and sqlite3_realloc64() +** is always aligned to at least an 8 byte boundary, or to a +** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time +** option is used. +** +** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] +** must be either NULL or else pointers obtained from a prior +** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have +** not yet been released. +** +** The application must not read or write any part of +** a block of memory after it has been released using +** [sqlite3_free()] or [sqlite3_realloc()]. +*/ +SQLITE_API void *sqlite3_malloc(int); +SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); +SQLITE_API void *sqlite3_realloc(void*, int); +SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); +SQLITE_API void sqlite3_free(void*); +SQLITE_API sqlite3_uint64 sqlite3_msize(void*); + +/* +** CAPI3REF: Memory Allocator Statistics +** +** SQLite provides these two interfaces for reporting on the status +** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] +** routines, which form the built-in memory allocation subsystem. +** +** ^The [sqlite3_memory_used()] routine returns the number of bytes +** of memory currently outstanding (malloced but not freed). +** ^The [sqlite3_memory_highwater()] routine returns the maximum +** value of [sqlite3_memory_used()] since the high-water mark +** was last reset. ^The values returned by [sqlite3_memory_used()] and +** [sqlite3_memory_highwater()] include any overhead +** added by SQLite in its implementation of [sqlite3_malloc()], +** but not overhead added by the any underlying system library +** routines that [sqlite3_malloc()] may call. +** +** ^The memory high-water mark is reset to the current value of +** [sqlite3_memory_used()] if and only if the parameter to +** [sqlite3_memory_highwater()] is true. ^The value returned +** by [sqlite3_memory_highwater(1)] is the high-water mark +** prior to the reset. +*/ +SQLITE_API sqlite3_int64 sqlite3_memory_used(void); +SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); + +/* +** CAPI3REF: Pseudo-Random Number Generator +** +** SQLite contains a high-quality pseudo-random number generator (PRNG) used to +** select random [ROWID | ROWIDs] when inserting new records into a table that +** already uses the largest possible [ROWID]. The PRNG is also used for +** the built-in random() and randomblob() SQL functions. This interface allows +** applications to access the same PRNG for other purposes. +** +** ^A call to this routine stores N bytes of randomness into buffer P. +** ^The P parameter can be a NULL pointer. +** +** ^If this routine has not been previously called or if the previous +** call had N less than one or a NULL pointer for P, then the PRNG is +** seeded using randomness obtained from the xRandomness method of +** the default [sqlite3_vfs] object. +** ^If the previous call to this routine had an N of 1 or more and a +** non-NULL P then the pseudo-randomness is generated +** internally and without recourse to the [sqlite3_vfs] xRandomness +** method. +*/ +SQLITE_API void sqlite3_randomness(int N, void *P); + +/* +** CAPI3REF: Compile-Time Authorization Callbacks +** METHOD: sqlite3 +** KEYWORDS: {authorizer callback} +** +** ^This routine registers an authorizer callback with a particular +** [database connection], supplied in the first argument. +** ^The authorizer callback is invoked as SQL statements are being compiled +** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], +** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], +** and [sqlite3_prepare16_v3()]. ^At various +** points during the compilation process, as logic is being created +** to perform various actions, the authorizer callback is invoked to +** see if those actions are allowed. ^The authorizer callback should +** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the +** specific action but allow the SQL statement to continue to be +** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be +** rejected with an error. ^If the authorizer callback returns +** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] +** then the [sqlite3_prepare_v2()] or equivalent call that triggered +** the authorizer will fail with an error message. +** +** When the callback returns [SQLITE_OK], that means the operation +** requested is ok. ^When the callback returns [SQLITE_DENY], the +** [sqlite3_prepare_v2()] or equivalent call that triggered the +** authorizer will fail with an error message explaining that +** access is denied. +** +** ^The first parameter to the authorizer callback is a copy of the third +** parameter to the sqlite3_set_authorizer() interface. ^The second parameter +** to the callback is an integer [SQLITE_COPY | action code] that specifies +** the particular action to be authorized. ^The third through sixth parameters +** to the callback are either NULL pointers or zero-terminated strings +** that contain additional details about the action to be authorized. +** Applications must always be prepared to encounter a NULL pointer in any +** of the third through the sixth parameters of the authorization callback. +** +** ^If the action code is [SQLITE_READ] +** and the callback returns [SQLITE_IGNORE] then the +** [prepared statement] statement is constructed to substitute +** a NULL value in place of the table column that would have +** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] +** return can be used to deny an untrusted user access to individual +** columns of a table. +** ^When a table is referenced by a [SELECT] but no column values are +** extracted from that table (for example in a query like +** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback +** is invoked once for that table with a column name that is an empty string. +** ^If the action code is [SQLITE_DELETE] and the callback returns +** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the +** [truncate optimization] is disabled and all rows are deleted individually. +** +** An authorizer is used when [sqlite3_prepare | preparing] +** SQL statements from an untrusted source, to ensure that the SQL statements +** do not try to access data they are not allowed to see, or that they do not +** try to execute malicious statements that damage the database. For +** example, an application may allow a user to enter arbitrary +** SQL queries for evaluation by a database. But the application does +** not want the user to be able to make arbitrary changes to the +** database. An authorizer could then be put in place while the +** user-entered SQL is being [sqlite3_prepare | prepared] that +** disallows everything except [SELECT] statements. +** +** Applications that need to process SQL from untrusted sources +** might also consider lowering resource limits using [sqlite3_limit()] +** and limiting database size using the [max_page_count] [PRAGMA] +** in addition to using an authorizer. +** +** ^(Only a single authorizer can be in place on a database connection +** at a time. Each call to sqlite3_set_authorizer overrides the +** previous call.)^ ^Disable the authorizer by installing a NULL callback. +** The authorizer is disabled by default. +** +** The authorizer callback must not do anything that will modify +** the database connection that invoked the authorizer callback. +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their +** database connections for the meaning of "modify" in this paragraph. +** +** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the +** statement might be re-prepared during [sqlite3_step()] due to a +** schema change. Hence, the application should ensure that the +** correct authorizer callback remains in place during the [sqlite3_step()]. +** +** ^Note that the authorizer callback is invoked only during +** [sqlite3_prepare()] or its variants. Authorization is not +** performed during statement evaluation in [sqlite3_step()], unless +** as stated in the previous paragraph, sqlite3_step() invokes +** sqlite3_prepare_v2() to reprepare a statement after a schema change. +*/ +SQLITE_API int sqlite3_set_authorizer( + sqlite3*, + int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), + void *pUserData +); + +/* +** CAPI3REF: Authorizer Return Codes +** +** The [sqlite3_set_authorizer | authorizer callback function] must +** return either [SQLITE_OK] or one of these two constants in order +** to signal SQLite whether or not the action is permitted. See the +** [sqlite3_set_authorizer | authorizer documentation] for additional +** information. +** +** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] +** returned from the [sqlite3_vtab_on_conflict()] interface. +*/ +#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ +#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ + +/* +** CAPI3REF: Authorizer Action Codes +** +** The [sqlite3_set_authorizer()] interface registers a callback function +** that is invoked to authorize certain SQL statement actions. The +** second parameter to the callback is an integer code that specifies +** what action is being authorized. These are the integer action codes that +** the authorizer callback may be passed. +** +** These action code values signify what kind of operation is to be +** authorized. The 3rd and 4th parameters to the authorization +** callback function will be parameters or NULL depending on which of these +** codes is used as the second parameter. ^(The 5th parameter to the +** authorizer callback is the name of the database ("main", "temp", +** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback +** is the name of the inner-most trigger or view that is responsible for +** the access attempt or NULL if this access attempt is directly from +** top-level SQL code. +*/ +/******************************************* 3rd ************ 4th ***********/ +#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ +#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ +#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ +#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ +#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ +#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ +#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ +#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ +#define SQLITE_DELETE 9 /* Table Name NULL */ +#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ +#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ +#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ +#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ +#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ +#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ +#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ +#define SQLITE_DROP_VIEW 17 /* View Name NULL */ +#define SQLITE_INSERT 18 /* Table Name NULL */ +#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ +#define SQLITE_READ 20 /* Table Name Column Name */ +#define SQLITE_SELECT 21 /* NULL NULL */ +#define SQLITE_TRANSACTION 22 /* Operation NULL */ +#define SQLITE_UPDATE 23 /* Table Name Column Name */ +#define SQLITE_ATTACH 24 /* Filename NULL */ +#define SQLITE_DETACH 25 /* Database Name NULL */ +#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ +#define SQLITE_REINDEX 27 /* Index Name NULL */ +#define SQLITE_ANALYZE 28 /* Table Name NULL */ +#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ +#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ +#define SQLITE_FUNCTION 31 /* NULL Function Name */ +#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ +#define SQLITE_COPY 0 /* No longer used */ +#define SQLITE_RECURSIVE 33 /* NULL NULL */ + +/* +** CAPI3REF: Deprecated Tracing And Profiling Functions +** DEPRECATED +** +** These routines are deprecated. Use the [sqlite3_trace_v2()] interface +** instead of the routines described here. +** +** These routines register callback functions that can be used for +** tracing and profiling the execution of SQL statements. +** +** ^The callback function registered by sqlite3_trace() is invoked at +** various times when an SQL statement is being run by [sqlite3_step()]. +** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the +** SQL statement text as the statement first begins executing. +** ^(Additional sqlite3_trace() callbacks might occur +** as each triggered subprogram is entered. The callbacks for triggers +** contain a UTF-8 SQL comment that identifies the trigger.)^ +** +** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit +** the length of [bound parameter] expansion in the output of sqlite3_trace(). +** +** ^The callback function registered by sqlite3_profile() is invoked +** as each SQL statement finishes. ^The profile callback contains +** the original statement text and an estimate of wall-clock time +** of how long that statement took to run. ^The profile callback +** time is in units of nanoseconds, however the current implementation +** is only capable of millisecond resolution so the six least significant +** digits in the time are meaningless. Future versions of SQLite +** might provide greater resolution on the profiler callback. Invoking +** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the +** profile callback. +*/ +SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, + void(*xTrace)(void*,const char*), void*); +SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, + void(*xProfile)(void*,const char*,sqlite3_uint64), void*); + +/* +** CAPI3REF: SQL Trace Event Codes +** KEYWORDS: SQLITE_TRACE +** +** These constants identify classes of events that can be monitored +** using the [sqlite3_trace_v2()] tracing logic. The M argument +** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of +** the following constants. ^The first argument to the trace callback +** is one of the following constants. +** +** New tracing constants may be added in future releases. +** +** ^A trace callback has four arguments: xCallback(T,C,P,X). +** ^The T argument is one of the integer type codes above. +** ^The C argument is a copy of the context pointer passed in as the +** fourth argument to [sqlite3_trace_v2()]. +** The P and X arguments are pointers whose meanings depend on T. +** +**
+** [[SQLITE_TRACE_STMT]]
SQLITE_TRACE_STMT
+**
^An SQLITE_TRACE_STMT callback is invoked when a prepared statement +** first begins running and possibly at other times during the +** execution of the prepared statement, such as at the start of each +** trigger subprogram. ^The P argument is a pointer to the +** [prepared statement]. ^The X argument is a pointer to a string which +** is the unexpanded SQL text of the prepared statement or an SQL comment +** that indicates the invocation of a trigger. ^The callback can compute +** the same text that would have been returned by the legacy [sqlite3_trace()] +** interface by using the X argument when X begins with "--" and invoking +** [sqlite3_expanded_sql(P)] otherwise. +** +** [[SQLITE_TRACE_PROFILE]]
SQLITE_TRACE_PROFILE
+**
^An SQLITE_TRACE_PROFILE callback provides approximately the same +** information as is provided by the [sqlite3_profile()] callback. +** ^The P argument is a pointer to the [prepared statement] and the +** X argument points to a 64-bit integer which is approximately +** the number of nanoseconds that the prepared statement took to run. +** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. +** +** [[SQLITE_TRACE_ROW]]
SQLITE_TRACE_ROW
+**
^An SQLITE_TRACE_ROW callback is invoked whenever a prepared +** statement generates a single row of result. +** ^The P argument is a pointer to the [prepared statement] and the +** X argument is unused. +** +** [[SQLITE_TRACE_CLOSE]]
SQLITE_TRACE_CLOSE
+**
^An SQLITE_TRACE_CLOSE callback is invoked when a database +** connection closes. +** ^The P argument is a pointer to the [database connection] object +** and the X argument is unused. +**
+*/ +#define SQLITE_TRACE_STMT 0x01 +#define SQLITE_TRACE_PROFILE 0x02 +#define SQLITE_TRACE_ROW 0x04 +#define SQLITE_TRACE_CLOSE 0x08 + +/* +** CAPI3REF: SQL Trace Hook +** METHOD: sqlite3 +** +** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback +** function X against [database connection] D, using property mask M +** and context pointer P. ^If the X callback is +** NULL or if the M mask is zero, then tracing is disabled. The +** M argument should be the bitwise OR-ed combination of +** zero or more [SQLITE_TRACE] constants. +** +** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P) +** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or +** sqlite3_trace_v2(D,M,X,P) for the [database connection] D. Each +** database connection may have at most one trace callback. +** +** ^The X callback is invoked whenever any of the events identified by +** mask M occur. ^The integer return value from the callback is currently +** ignored, though this may change in future releases. Callback +** implementations should return zero to ensure future compatibility. +** +** ^A trace callback is invoked with four arguments: callback(T,C,P,X). +** ^The T argument is one of the [SQLITE_TRACE] +** constants to indicate why the callback was invoked. +** ^The C argument is a copy of the context pointer. +** The P and X arguments are pointers whose meanings depend on T. +** +** The sqlite3_trace_v2() interface is intended to replace the legacy +** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which +** are deprecated. +*/ +SQLITE_API int sqlite3_trace_v2( + sqlite3*, + unsigned uMask, + int(*xCallback)(unsigned,void*,void*,void*), + void *pCtx +); + +/* +** CAPI3REF: Query Progress Callbacks +** METHOD: sqlite3 +** +** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback +** function X to be invoked periodically during long running calls to +** [sqlite3_step()] and [sqlite3_prepare()] and similar for +** database connection D. An example use for this +** interface is to keep a GUI updated during a large query. +** +** ^The parameter P is passed through as the only parameter to the +** callback function X. ^The parameter N is the approximate number of +** [virtual machine instructions] that are evaluated between successive +** invocations of the callback X. ^If N is less than one then the progress +** handler is disabled. +** +** ^Only a single progress handler may be defined at one time per +** [database connection]; setting a new progress handler cancels the +** old one. ^Setting parameter X to NULL disables the progress handler. +** ^The progress handler is also disabled by setting N to a value less +** than 1. +** +** ^If the progress callback returns non-zero, the operation is +** interrupted. This feature can be used to implement a +** "Cancel" button on a GUI progress dialog box. +** +** The progress handler callback must not do anything that will modify +** the database connection that invoked the progress handler. +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their +** database connections for the meaning of "modify" in this paragraph. +** +** The progress handler callback would originally only be invoked from the +** bytecode engine. It still might be invoked during [sqlite3_prepare()] +** and similar because those routines might force a reparse of the schema +** which involves running the bytecode engine. However, beginning with +** SQLite version 3.41.0, the progress handler callback might also be +** invoked directly from [sqlite3_prepare()] while analyzing and generating +** code for complex queries. +*/ +SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); + +/* +** CAPI3REF: Opening A New Database Connection +** CONSTRUCTOR: sqlite3 +** +** ^These routines open an SQLite database file as specified by the +** filename argument. ^The filename argument is interpreted as UTF-8 for +** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte +** order for sqlite3_open16(). ^(A [database connection] handle is usually +** returned in *ppDb, even if an error occurs. The only exception is that +** if SQLite is unable to allocate memory to hold the [sqlite3] object, +** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] +** object.)^ ^(If the database is opened (and/or created) successfully, then +** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The +** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain +** an English language description of the error following a failure of any +** of the sqlite3_open() routines. +** +** ^The default encoding will be UTF-8 for databases created using +** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases +** created using sqlite3_open16() will be UTF-16 in the native byte order. +** +** Whether or not an error occurs when it is opened, resources +** associated with the [database connection] handle should be released by +** passing it to [sqlite3_close()] when it is no longer required. +** +** The sqlite3_open_v2() interface works like sqlite3_open() +** except that it accepts two additional parameters for additional control +** over the new database connection. ^(The flags parameter to +** sqlite3_open_v2() must include, at a minimum, one of the following +** three flag combinations:)^ +** +**
+** ^(
[SQLITE_OPEN_READONLY]
+**
The database is opened in read-only mode. If the database does +** not already exist, an error is returned.
)^ +** +** ^(
[SQLITE_OPEN_READWRITE]
+**
The database is opened for reading and writing if possible, or +** reading only if the file is write protected by the operating +** system. In either case the database must already exist, otherwise +** an error is returned. For historical reasons, if opening in +** read-write mode fails due to OS-level permissions, an attempt is +** made to open it in read-only mode. [sqlite3_db_readonly()] can be +** used to determine whether the database is actually +** read-write.
)^ +** +** ^(
[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
+**
The database is opened for reading and writing, and is created if +** it does not already exist. This is the behavior that is always used for +** sqlite3_open() and sqlite3_open16().
)^ +**
+** +** In addition to the required flags, the following optional flags are +** also supported: +** +**
+** ^(
[SQLITE_OPEN_URI]
+**
The filename can be interpreted as a URI if this flag is set.
)^ +** +** ^(
[SQLITE_OPEN_MEMORY]
+**
The database will be opened as an in-memory database. The database +** is named by the "filename" argument for the purposes of cache-sharing, +** if shared cache mode is enabled, but the "filename" is otherwise ignored. +**
)^ +** +** ^(
[SQLITE_OPEN_NOMUTEX]
+**
The new database connection will use the "multi-thread" +** [threading mode].)^ This means that separate threads are allowed +** to use SQLite at the same time, as long as each thread is using +** a different [database connection]. +** +** ^(
[SQLITE_OPEN_FULLMUTEX]
+**
The new database connection will use the "serialized" +** [threading mode].)^ This means the multiple threads can safely +** attempt to use the same database connection at the same time. +** (Mutexes will block any actual concurrency, but in this mode +** there is no harm in trying.) +** +** ^(
[SQLITE_OPEN_SHAREDCACHE]
+**
The database is opened [shared cache] enabled, overriding +** the default shared cache setting provided by +** [sqlite3_enable_shared_cache()].)^ +** The [use of shared cache mode is discouraged] and hence shared cache +** capabilities may be omitted from many builds of SQLite. In such cases, +** this option is a no-op. +** +** ^(
[SQLITE_OPEN_PRIVATECACHE]
+**
The database is opened [shared cache] disabled, overriding +** the default shared cache setting provided by +** [sqlite3_enable_shared_cache()].)^ +** +** [[OPEN_EXRESCODE]] ^(
[SQLITE_OPEN_EXRESCODE]
+**
The database connection comes up in "extended result code mode". +** In other words, the database behaves has if +** [sqlite3_extended_result_codes(db,1)] where called on the database +** connection as soon as the connection is created. In addition to setting +** the extended result code mode, this flag also causes [sqlite3_open_v2()] +** to return an extended result code.
+** +** [[OPEN_NOFOLLOW]] ^(
[SQLITE_OPEN_NOFOLLOW]
+**
The database filename is not allowed to contain a symbolic link
+**
)^ +** +** If the 3rd parameter to sqlite3_open_v2() is not one of the +** required combinations shown above optionally combined with other +** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] +** then the behavior is undefined. Historic versions of SQLite +** have silently ignored surplus bits in the flags parameter to +** sqlite3_open_v2(), however that behavior might not be carried through +** into future versions of SQLite and so applications should not rely +** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op +** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause +** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE +** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not +** by sqlite3_open_v2(). +** +** ^The fourth parameter to sqlite3_open_v2() is the name of the +** [sqlite3_vfs] object that defines the operating system interface that +** the new database connection should use. ^If the fourth parameter is +** a NULL pointer then the default [sqlite3_vfs] object is used. +** +** ^If the filename is ":memory:", then a private, temporary in-memory database +** is created for the connection. ^This in-memory database will vanish when +** the database connection is closed. Future versions of SQLite might +** make use of additional special filenames that begin with the ":" character. +** It is recommended that when a database filename actually does begin with +** a ":" character you should prefix the filename with a pathname such as +** "./" to avoid ambiguity. +** +** ^If the filename is an empty string, then a private, temporary +** on-disk database will be created. ^This private database will be +** automatically deleted as soon as the database connection is closed. +** +** [[URI filenames in sqlite3_open()]]

URI Filenames

+** +** ^If [URI filename] interpretation is enabled, and the filename argument +** begins with "file:", then the filename is interpreted as a URI. ^URI +** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is +** set in the third argument to sqlite3_open_v2(), or if it has +** been enabled globally using the [SQLITE_CONFIG_URI] option with the +** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. +** URI filename interpretation is turned off +** by default, but future releases of SQLite might enable URI filename +** interpretation by default. See "[URI filenames]" for additional +** information. +** +** URI filenames are parsed according to RFC 3986. ^If the URI contains an +** authority, then it must be either an empty string or the string +** "localhost". ^If the authority is not an empty string or "localhost", an +** error is returned to the caller. ^The fragment component of a URI, if +** present, is ignored. +** +** ^SQLite uses the path component of the URI as the name of the disk file +** which contains the database. ^If the path begins with a '/' character, +** then it is interpreted as an absolute path. ^If the path does not begin +** with a '/' (meaning that the authority section is omitted from the URI) +** then the path is interpreted as a relative path. +** ^(On windows, the first component of an absolute path +** is a drive specification (e.g. "C:").)^ +** +** [[core URI query parameters]] +** The query component of a URI may contain parameters that are interpreted +** either by SQLite itself, or by a [VFS | custom VFS implementation]. +** SQLite and its built-in [VFSes] interpret the +** following query parameters: +** +**
    +**
  • vfs: ^The "vfs" parameter may be used to specify the name of +** a VFS object that provides the operating system interface that should +** be used to access the database file on disk. ^If this option is set to +** an empty string the default VFS object is used. ^Specifying an unknown +** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is +** present, then the VFS specified by the option takes precedence over +** the value passed as the fourth parameter to sqlite3_open_v2(). +** +**
  • mode: ^(The mode parameter may be set to either "ro", "rw", +** "rwc", or "memory". Attempting to set it to any other value is +** an error)^. +** ^If "ro" is specified, then the database is opened for read-only +** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the +** third argument to sqlite3_open_v2(). ^If the mode option is set to +** "rw", then the database is opened for read-write (but not create) +** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had +** been set. ^Value "rwc" is equivalent to setting both +** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is +** set to "memory" then a pure [in-memory database] that never reads +** or writes from disk is used. ^It is an error to specify a value for +** the mode parameter that is less restrictive than that specified by +** the flags passed in the third parameter to sqlite3_open_v2(). +** +**
  • cache: ^The cache parameter may be set to either "shared" or +** "private". ^Setting it to "shared" is equivalent to setting the +** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to +** sqlite3_open_v2(). ^Setting the cache parameter to "private" is +** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. +** ^If sqlite3_open_v2() is used and the "cache" parameter is present in +** a URI filename, its value overrides any behavior requested by setting +** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. +** +**
  • psow: ^The psow parameter indicates whether or not the +** [powersafe overwrite] property does or does not apply to the +** storage media on which the database file resides. +** +**
  • nolock: ^The nolock parameter is a boolean query parameter +** which if set disables file locking in rollback journal modes. This +** is useful for accessing a database on a filesystem that does not +** support locking. Caution: Database corruption might result if two +** or more processes write to the same database and any one of those +** processes uses nolock=1. +** +**
  • immutable: ^The immutable parameter is a boolean query +** parameter that indicates that the database file is stored on +** read-only media. ^When immutable is set, SQLite assumes that the +** database file cannot be changed, even by a process with higher +** privilege, and so the database is opened read-only and all locking +** and change detection is disabled. Caution: Setting the immutable +** property on a database file that does in fact change can result +** in incorrect query results and/or [SQLITE_CORRUPT] errors. +** See also: [SQLITE_IOCAP_IMMUTABLE]. +** +**
+** +** ^Specifying an unknown parameter in the query component of a URI is not an +** error. Future versions of SQLite might understand additional query +** parameters. See "[query parameters with special meaning to SQLite]" for +** additional information. +** +** [[URI filename examples]]

URI filename examples

+** +** +**
URI filenames Results +**
file:data.db +** Open the file "data.db" in the current directory. +**
file:/home/fred/data.db
+** file:///home/fred/data.db
+** file://localhost/home/fred/data.db
+** Open the database file "/home/fred/data.db". +**
file://darkstar/home/fred/data.db +** An error. "darkstar" is not a recognized authority. +**
+** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db +** Windows only: Open the file "data.db" on fred's desktop on drive +** C:. Note that the %20 escaping in this example is not strictly +** necessary - space characters can be used literally +** in URI filenames. +**
file:data.db?mode=ro&cache=private +** Open file "data.db" in the current directory for read-only access. +** Regardless of whether or not shared-cache mode is enabled by +** default, use a private cache. +**
file:/home/fred/data.db?vfs=unix-dotfile +** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" +** that uses dot-files in place of posix advisory locking. +**
file:data.db?mode=readonly +** An error. "readonly" is not a valid option for the "mode" parameter. +** Use "ro" instead: "file:data.db?mode=ro". +**
+** +** ^URI hexadecimal escape sequences (%HH) are supported within the path and +** query components of a URI. A hexadecimal escape sequence consists of a +** percent sign - "%" - followed by exactly two hexadecimal digits +** specifying an octet value. ^Before the path or query components of a +** URI filename are interpreted, they are encoded using UTF-8 and all +** hexadecimal escape sequences replaced by a single byte containing the +** corresponding octet. If this process generates an invalid UTF-8 encoding, +** the results are undefined. +** +** Note to Windows users: The encoding used for the filename argument +** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever +** codepage is currently defined. Filenames containing international +** characters must be converted to UTF-8 prior to passing them into +** sqlite3_open() or sqlite3_open_v2(). +** +** Note to Windows Runtime users: The temporary directory must be set +** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various +** features that require the use of temporary files may fail. +** +** See also: [sqlite3_temp_directory] +*/ +SQLITE_API int sqlite3_open( + const char *filename, /* Database filename (UTF-8) */ + sqlite3 **ppDb /* OUT: SQLite db handle */ +); +SQLITE_API int sqlite3_open16( + const void *filename, /* Database filename (UTF-16) */ + sqlite3 **ppDb /* OUT: SQLite db handle */ +); +SQLITE_API int sqlite3_open_v2( + const char *filename, /* Database filename (UTF-8) */ + sqlite3 **ppDb, /* OUT: SQLite db handle */ + int flags, /* Flags */ + const char *zVfs /* Name of VFS module to use */ +); + +/* +** CAPI3REF: Obtain Values For URI Parameters +** +** These are utility routines, useful to [VFS|custom VFS implementations], +** that check if a database file was a URI that contained a specific query +** parameter, and if so obtains the value of that query parameter. +** +** The first parameter to these interfaces (hereafter referred to +** as F) must be one of: +**
    +**
  • A database filename pointer created by the SQLite core and +** passed into the xOpen() method of a VFS implementation, or +**
  • A filename obtained from [sqlite3_db_filename()], or +**
  • A new filename constructed using [sqlite3_create_filename()]. +**
+** If the F parameter is not one of the above, then the behavior is +** undefined and probably undesirable. Older versions of SQLite were +** more tolerant of invalid F parameters than newer versions. +** +** If F is a suitable filename (as described in the previous paragraph) +** and if P is the name of the query parameter, then +** sqlite3_uri_parameter(F,P) returns the value of the P +** parameter if it exists or a NULL pointer if P does not appear as a +** query parameter on F. If P is a query parameter of F and it +** has no explicit value, then sqlite3_uri_parameter(F,P) returns +** a pointer to an empty string. +** +** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean +** parameter and returns true (1) or false (0) according to the value +** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the +** value of query parameter P is one of "yes", "true", or "on" in any +** case or if the value begins with a non-zero number. The +** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of +** query parameter P is one of "no", "false", or "off" in any case or +** if the value begins with a numeric zero. If P is not a query +** parameter on F or if the value of P does not match any of the +** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). +** +** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a +** 64-bit signed integer and returns that integer, or D if P does not +** exist. If the value of P is something other than an integer, then +** zero is returned. +** +** The sqlite3_uri_key(F,N) returns a pointer to the name (not +** the value) of the N-th query parameter for filename F, or a NULL +** pointer if N is less than zero or greater than the number of query +** parameters minus 1. The N value is zero-based so N should be 0 to obtain +** the name of the first query parameter, 1 for the second parameter, and +** so forth. +** +** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and +** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and +** is not a database file pathname pointer that the SQLite core passed +** into the xOpen VFS method, then the behavior of this routine is undefined +** and probably undesirable. +** +** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F +** parameter can also be the name of a rollback journal file or WAL file +** in addition to the main database file. Prior to version 3.31.0, these +** routines would only work if F was the name of the main database file. +** When the F parameter is the name of the rollback journal or WAL file, +** it has access to all the same query parameters as were found on the +** main database file. +** +** See the [URI filename] documentation for additional information. +*/ +SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam); +SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault); +SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64); +SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N); + +/* +** CAPI3REF: Translate filenames +** +** These routines are available to [VFS|custom VFS implementations] for +** translating filenames between the main database file, the journal file, +** and the WAL file. +** +** If F is the name of an sqlite database file, journal file, or WAL file +** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) +** returns the name of the corresponding database file. +** +** If F is the name of an sqlite database file, journal file, or WAL file +** passed by the SQLite core into the VFS, or if F is a database filename +** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) +** returns the name of the corresponding rollback journal file. +** +** If F is the name of an sqlite database file, journal file, or WAL file +** that was passed by the SQLite core into the VFS, or if F is a database +** filename obtained from [sqlite3_db_filename()], then +** sqlite3_filename_wal(F) returns the name of the corresponding +** WAL file. +** +** In all of the above, if F is not the name of a database, journal or WAL +** filename passed into the VFS from the SQLite core and F is not the +** return value from [sqlite3_db_filename()], then the result is +** undefined and is likely a memory access violation. +*/ +SQLITE_API const char *sqlite3_filename_database(sqlite3_filename); +SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename); +SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename); + +/* +** CAPI3REF: Database File Corresponding To A Journal +** +** ^If X is the name of a rollback or WAL-mode journal file that is +** passed into the xOpen method of [sqlite3_vfs], then +** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] +** object that represents the main database file. +** +** This routine is intended for use in custom [VFS] implementations +** only. It is not a general-purpose interface. +** The argument sqlite3_file_object(X) must be a filename pointer that +** has been passed into [sqlite3_vfs].xOpen method where the +** flags parameter to xOpen contains one of the bits +** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use +** of this routine results in undefined and probably undesirable +** behavior. +*/ +SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*); + +/* +** CAPI3REF: Create and Destroy VFS Filenames +** +** These interfaces are provided for use by [VFS shim] implementations and +** are not useful outside of that context. +** +** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of +** database filename D with corresponding journal file J and WAL file W and +** with N URI parameters key/values pairs in the array P. The result from +** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that +** is safe to pass to routines like: +**
    +**
  • [sqlite3_uri_parameter()], +**
  • [sqlite3_uri_boolean()], +**
  • [sqlite3_uri_int64()], +**
  • [sqlite3_uri_key()], +**
  • [sqlite3_filename_database()], +**
  • [sqlite3_filename_journal()], or +**
  • [sqlite3_filename_wal()]. +**
+** If a memory allocation error occurs, sqlite3_create_filename() might +** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) +** must be released by a corresponding call to sqlite3_free_filename(Y). +** +** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array +** of 2*N pointers to strings. Each pair of pointers in this array corresponds +** to a key and value for a query parameter. The P parameter may be a NULL +** pointer if N is zero. None of the 2*N pointers in the P array may be +** NULL pointers and key pointers should not be empty strings. +** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may +** be NULL pointers, though they can be empty strings. +** +** The sqlite3_free_filename(Y) routine releases a memory allocation +** previously obtained from sqlite3_create_filename(). Invoking +** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. +** +** If the Y parameter to sqlite3_free_filename(Y) is anything other +** than a NULL pointer or a pointer previously acquired from +** sqlite3_create_filename(), then bad things such as heap +** corruption or segfaults may occur. The value Y should not be +** used again after sqlite3_free_filename(Y) has been called. This means +** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, +** then the corresponding [sqlite3_module.xClose() method should also be +** invoked prior to calling sqlite3_free_filename(Y). +*/ +SQLITE_API sqlite3_filename sqlite3_create_filename( + const char *zDatabase, + const char *zJournal, + const char *zWal, + int nParam, + const char **azParam +); +SQLITE_API void sqlite3_free_filename(sqlite3_filename); + +/* +** CAPI3REF: Error Codes And Messages +** METHOD: sqlite3 +** +** ^If the most recent sqlite3_* API call associated with +** [database connection] D failed, then the sqlite3_errcode(D) interface +** returns the numeric [result code] or [extended result code] for that +** API call. +** ^The sqlite3_extended_errcode() +** interface is the same except that it always returns the +** [extended result code] even when extended result codes are +** disabled. +** +** The values returned by sqlite3_errcode() and/or +** sqlite3_extended_errcode() might change with each API call. +** Except, there are some interfaces that are guaranteed to never +** change the value of the error code. The error-code preserving +** interfaces include the following: +** +**
    +**
  • sqlite3_errcode() +**
  • sqlite3_extended_errcode() +**
  • sqlite3_errmsg() +**
  • sqlite3_errmsg16() +**
  • sqlite3_error_offset() +**
+** +** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language +** text that describes the error, as either UTF-8 or UTF-16 respectively, +** or NULL if no error message is available. +** (See how SQLite handles [invalid UTF] for exceptions to this rule.) +** ^(Memory to hold the error message string is managed internally. +** The application does not need to worry about freeing the result. +** However, the error string might be overwritten or deallocated by +** subsequent calls to other SQLite interface functions.)^ +** +** ^The sqlite3_errstr(E) interface returns the English-language text +** that describes the [result code] E, as UTF-8, or NULL if E is not an +** result code for which a text error message is available. +** ^(Memory to hold the error message string is managed internally +** and must not be freed by the application)^. +** +** ^If the most recent error references a specific token in the input +** SQL, the sqlite3_error_offset() interface returns the byte offset +** of the start of that token. ^The byte offset returned by +** sqlite3_error_offset() assumes that the input SQL is UTF8. +** ^If the most recent error does not reference a specific token in the input +** SQL, then the sqlite3_error_offset() function returns -1. +** +** When the serialized [threading mode] is in use, it might be the +** case that a second error occurs on a separate thread in between +** the time of the first error and the call to these interfaces. +** When that happens, the second error will be reported since these +** interfaces always report the most recent result. To avoid +** this, each thread can obtain exclusive use of the [database connection] D +** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning +** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after +** all calls to the interfaces listed here are completed. +** +** If an interface fails with SQLITE_MISUSE, that means the interface +** was invoked incorrectly by the application. In that case, the +** error code and message may or may not be set. +*/ +SQLITE_API int sqlite3_errcode(sqlite3 *db); +SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); +SQLITE_API const char *sqlite3_errmsg(sqlite3*); +SQLITE_API const void *sqlite3_errmsg16(sqlite3*); +SQLITE_API const char *sqlite3_errstr(int); +SQLITE_API int sqlite3_error_offset(sqlite3 *db); + +/* +** CAPI3REF: Prepared Statement Object +** KEYWORDS: {prepared statement} {prepared statements} +** +** An instance of this object represents a single SQL statement that +** has been compiled into binary form and is ready to be evaluated. +** +** Think of each SQL statement as a separate computer program. The +** original SQL text is source code. A prepared statement object +** is the compiled object code. All SQL must be converted into a +** prepared statement before it can be run. +** +** The life-cycle of a prepared statement object usually goes like this: +** +**
    +**
  1. Create the prepared statement object using [sqlite3_prepare_v2()]. +**
  2. Bind values to [parameters] using the sqlite3_bind_*() +** interfaces. +**
  3. Run the SQL by calling [sqlite3_step()] one or more times. +**
  4. Reset the prepared statement using [sqlite3_reset()] then go back +** to step 2. Do this zero or more times. +**
  5. Destroy the object using [sqlite3_finalize()]. +**
+*/ +typedef struct sqlite3_stmt sqlite3_stmt; + +/* +** CAPI3REF: Run-time Limits +** METHOD: sqlite3 +** +** ^(This interface allows the size of various constructs to be limited +** on a connection by connection basis. The first parameter is the +** [database connection] whose limit is to be set or queried. The +** second parameter is one of the [limit categories] that define a +** class of constructs to be size limited. The third parameter is the +** new limit for that construct.)^ +** +** ^If the new limit is a negative number, the limit is unchanged. +** ^(For each limit category SQLITE_LIMIT_NAME there is a +** [limits | hard upper bound] +** set at compile-time by a C preprocessor macro called +** [limits | SQLITE_MAX_NAME]. +** (The "_LIMIT_" in the name is changed to "_MAX_".))^ +** ^Attempts to increase a limit above its hard upper bound are +** silently truncated to the hard upper bound. +** +** ^Regardless of whether or not the limit was changed, the +** [sqlite3_limit()] interface returns the prior value of the limit. +** ^Hence, to find the current value of a limit without changing it, +** simply invoke this interface with the third parameter set to -1. +** +** Run-time limits are intended for use in applications that manage +** both their own internal database and also databases that are controlled +** by untrusted external sources. An example application might be a +** web browser that has its own databases for storing history and +** separate databases controlled by JavaScript applications downloaded +** off the Internet. The internal databases can be given the +** large, default limits. Databases managed by external sources can +** be given much smaller limits designed to prevent a denial of service +** attack. Developers might also want to use the [sqlite3_set_authorizer()] +** interface to further control untrusted SQL. The size of the database +** created by an untrusted script can be contained using the +** [max_page_count] [PRAGMA]. +** +** New run-time limit categories may be added in future releases. +*/ +SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); + +/* +** CAPI3REF: Run-Time Limit Categories +** KEYWORDS: {limit category} {*limit categories} +** +** These constants define various performance limits +** that can be lowered at run-time using [sqlite3_limit()]. +** The synopsis of the meanings of the various limits is shown below. +** Additional information is available at [limits | Limits in SQLite]. +** +**
+** [[SQLITE_LIMIT_LENGTH]] ^(
SQLITE_LIMIT_LENGTH
+**
The maximum size of any string or BLOB or table row, in bytes.
)^ +** +** [[SQLITE_LIMIT_SQL_LENGTH]] ^(
SQLITE_LIMIT_SQL_LENGTH
+**
The maximum length of an SQL statement, in bytes.
)^ +** +** [[SQLITE_LIMIT_COLUMN]] ^(
SQLITE_LIMIT_COLUMN
+**
The maximum number of columns in a table definition or in the +** result set of a [SELECT] or the maximum number of columns in an index +** or in an ORDER BY or GROUP BY clause.
)^ +** +** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(
SQLITE_LIMIT_EXPR_DEPTH
+**
The maximum depth of the parse tree on any expression.
)^ +** +** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(
SQLITE_LIMIT_COMPOUND_SELECT
+**
The maximum number of terms in a compound SELECT statement.
)^ +** +** [[SQLITE_LIMIT_VDBE_OP]] ^(
SQLITE_LIMIT_VDBE_OP
+**
The maximum number of instructions in a virtual machine program +** used to implement an SQL statement. If [sqlite3_prepare_v2()] or +** the equivalent tries to allocate space for more than this many opcodes +** in a single prepared statement, an SQLITE_NOMEM error is returned.
)^ +** +** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(
SQLITE_LIMIT_FUNCTION_ARG
+**
The maximum number of arguments on a function.
)^ +** +** [[SQLITE_LIMIT_ATTACHED]] ^(
SQLITE_LIMIT_ATTACHED
+**
The maximum number of [ATTACH | attached databases].)^
+** +** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] +** ^(
SQLITE_LIMIT_LIKE_PATTERN_LENGTH
+**
The maximum length of the pattern argument to the [LIKE] or +** [GLOB] operators.
)^ +** +** [[SQLITE_LIMIT_VARIABLE_NUMBER]] +** ^(
SQLITE_LIMIT_VARIABLE_NUMBER
+**
The maximum index number of any [parameter] in an SQL statement.)^ +** +** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(
SQLITE_LIMIT_TRIGGER_DEPTH
+**
The maximum depth of recursion for triggers.
)^ +** +** [[SQLITE_LIMIT_WORKER_THREADS]] ^(
SQLITE_LIMIT_WORKER_THREADS
+**
The maximum number of auxiliary worker threads that a single +** [prepared statement] may start.
)^ +**
+*/ +#define SQLITE_LIMIT_LENGTH 0 +#define SQLITE_LIMIT_SQL_LENGTH 1 +#define SQLITE_LIMIT_COLUMN 2 +#define SQLITE_LIMIT_EXPR_DEPTH 3 +#define SQLITE_LIMIT_COMPOUND_SELECT 4 +#define SQLITE_LIMIT_VDBE_OP 5 +#define SQLITE_LIMIT_FUNCTION_ARG 6 +#define SQLITE_LIMIT_ATTACHED 7 +#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 +#define SQLITE_LIMIT_VARIABLE_NUMBER 9 +#define SQLITE_LIMIT_TRIGGER_DEPTH 10 +#define SQLITE_LIMIT_WORKER_THREADS 11 + +/* +** CAPI3REF: Prepare Flags +** +** These constants define various flags that can be passed into +** "prepFlags" parameter of the [sqlite3_prepare_v3()] and +** [sqlite3_prepare16_v3()] interfaces. +** +** New flags may be added in future releases of SQLite. +** +**
+** [[SQLITE_PREPARE_PERSISTENT]] ^(
SQLITE_PREPARE_PERSISTENT
+**
The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner +** that the prepared statement will be retained for a long time and +** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] +** and [sqlite3_prepare16_v3()] assume that the prepared statement will +** be used just once or at most a few times and then destroyed using +** [sqlite3_finalize()] relatively soon. The current implementation acts +** on this hint by avoiding the use of [lookaside memory] so as not to +** deplete the limited store of lookaside memory. Future versions of +** SQLite may act on this hint differently. +** +** [[SQLITE_PREPARE_NORMALIZE]]
SQLITE_PREPARE_NORMALIZE
+**
The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used +** to be required for any prepared statement that wanted to use the +** [sqlite3_normalized_sql()] interface. However, the +** [sqlite3_normalized_sql()] interface is now available to all +** prepared statements, regardless of whether or not they use this +** flag. +** +** [[SQLITE_PREPARE_NO_VTAB]]
SQLITE_PREPARE_NO_VTAB
+**
The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler +** to return an error (error code SQLITE_ERROR) if the statement uses +** any virtual tables. +**
+*/ +#define SQLITE_PREPARE_PERSISTENT 0x01 +#define SQLITE_PREPARE_NORMALIZE 0x02 +#define SQLITE_PREPARE_NO_VTAB 0x04 + +/* +** CAPI3REF: Compiling An SQL Statement +** KEYWORDS: {SQL statement compiler} +** METHOD: sqlite3 +** CONSTRUCTOR: sqlite3_stmt +** +** To execute an SQL statement, it must first be compiled into a byte-code +** program using one of these routines. Or, in other words, these routines +** are constructors for the [prepared statement] object. +** +** The preferred routine to use is [sqlite3_prepare_v2()]. The +** [sqlite3_prepare()] interface is legacy and should be avoided. +** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used +** for special purposes. +** +** The use of the UTF-8 interfaces is preferred, as SQLite currently +** does all parsing using UTF-8. The UTF-16 interfaces are provided +** as a convenience. The UTF-16 interfaces work by converting the +** input text into UTF-8, then invoking the corresponding UTF-8 interface. +** +** The first argument, "db", is a [database connection] obtained from a +** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or +** [sqlite3_open16()]. The database connection must not have been closed. +** +** The second argument, "zSql", is the statement to be compiled, encoded +** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), +** and sqlite3_prepare_v3() +** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), +** and sqlite3_prepare16_v3() use UTF-16. +** +** ^If the nByte argument is negative, then zSql is read up to the +** first zero terminator. ^If nByte is positive, then it is the +** number of bytes read from zSql. ^If nByte is zero, then no prepared +** statement is generated. +** If the caller knows that the supplied string is nul-terminated, then +** there is a small performance advantage to passing an nByte parameter that +** is the number of bytes in the input string including +** the nul-terminator. +** +** ^If pzTail is not NULL then *pzTail is made to point to the first byte +** past the end of the first SQL statement in zSql. These routines only +** compile the first statement in zSql, so *pzTail is left pointing to +** what remains uncompiled. +** +** ^*ppStmt is left pointing to a compiled [prepared statement] that can be +** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set +** to NULL. ^If the input text contains no SQL (if the input is an empty +** string or a comment) then *ppStmt is set to NULL. +** The calling procedure is responsible for deleting the compiled +** SQL statement using [sqlite3_finalize()] after it has finished with it. +** ppStmt may not be NULL. +** +** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; +** otherwise an [error code] is returned. +** +** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), +** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. +** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) +** are retained for backwards compatibility, but their use is discouraged. +** ^In the "vX" interfaces, the prepared statement +** that is returned (the [sqlite3_stmt] object) contains a copy of the +** original SQL text. This causes the [sqlite3_step()] interface to +** behave differently in three ways: +** +**
    +**
  1. +** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it +** always used to do, [sqlite3_step()] will automatically recompile the SQL +** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] +** retries will occur before sqlite3_step() gives up and returns an error. +**
    2. +** +**
  2. +** ^When an error occurs, [sqlite3_step()] will return one of the detailed +** [error codes] or [extended error codes]. ^The legacy behavior was that +** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code +** and the application would have to make a second call to [sqlite3_reset()] +** in order to find the underlying cause of the problem. With the "v2" prepare +** interfaces, the underlying reason for the error is returned immediately. +**
    3. +** +**
  3. +** ^If the specific value bound to a [parameter | host parameter] in the +** WHERE clause might influence the choice of query plan for a statement, +** then the statement will be automatically recompiled, as if there had been +** a schema change, on the first [sqlite3_step()] call following any change +** to the [sqlite3_bind_text | bindings] of that [parameter]. +** ^The specific value of a WHERE-clause [parameter] might influence the +** choice of query plan if the parameter is the left-hand side of a [LIKE] +** or [GLOB] operator or if the parameter is compared to an indexed column +** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. +**
    4. +**
+** +**

^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having +** the extra prepFlags parameter, which is a bit array consisting of zero or +** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The +** sqlite3_prepare_v2() interface works exactly the same as +** sqlite3_prepare_v3() with a zero prepFlags parameter. +*/ +SQLITE_API int sqlite3_prepare( + sqlite3 *db, /* Database handle */ + const char *zSql, /* SQL statement, UTF-8 encoded */ + int nByte, /* Maximum length of zSql in bytes. */ + sqlite3_stmt **ppStmt, /* OUT: Statement handle */ + const char **pzTail /* OUT: Pointer to unused portion of zSql */ +); +SQLITE_API int sqlite3_prepare_v2( + sqlite3 *db, /* Database handle */ + const char *zSql, /* SQL statement, UTF-8 encoded */ + int nByte, /* Maximum length of zSql in bytes. */ + sqlite3_stmt **ppStmt, /* OUT: Statement handle */ + const char **pzTail /* OUT: Pointer to unused portion of zSql */ +); +SQLITE_API int sqlite3_prepare_v3( + sqlite3 *db, /* Database handle */ + const char *zSql, /* SQL statement, UTF-8 encoded */ + int nByte, /* Maximum length of zSql in bytes. */ + unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ + sqlite3_stmt **ppStmt, /* OUT: Statement handle */ + const char **pzTail /* OUT: Pointer to unused portion of zSql */ +); +SQLITE_API int sqlite3_prepare16( + sqlite3 *db, /* Database handle */ + const void *zSql, /* SQL statement, UTF-16 encoded */ + int nByte, /* Maximum length of zSql in bytes. */ + sqlite3_stmt **ppStmt, /* OUT: Statement handle */ + const void **pzTail /* OUT: Pointer to unused portion of zSql */ +); +SQLITE_API int sqlite3_prepare16_v2( + sqlite3 *db, /* Database handle */ + const void *zSql, /* SQL statement, UTF-16 encoded */ + int nByte, /* Maximum length of zSql in bytes. */ + sqlite3_stmt **ppStmt, /* OUT: Statement handle */ + const void **pzTail /* OUT: Pointer to unused portion of zSql */ +); +SQLITE_API int sqlite3_prepare16_v3( + sqlite3 *db, /* Database handle */ + const void *zSql, /* SQL statement, UTF-16 encoded */ + int nByte, /* Maximum length of zSql in bytes. */ + unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ + sqlite3_stmt **ppStmt, /* OUT: Statement handle */ + const void **pzTail /* OUT: Pointer to unused portion of zSql */ +); + +/* +** CAPI3REF: Retrieving Statement SQL +** METHOD: sqlite3_stmt +** +** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 +** SQL text used to create [prepared statement] P if P was +** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], +** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. +** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 +** string containing the SQL text of prepared statement P with +** [bound parameters] expanded. +** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 +** string containing the normalized SQL text of prepared statement P. The +** semantics used to normalize a SQL statement are unspecified and subject +** to change. At a minimum, literal values will be replaced with suitable +** placeholders. +** +** ^(For example, if a prepared statement is created using the SQL +** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 +** and parameter :xyz is unbound, then sqlite3_sql() will return +** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() +** will return "SELECT 2345,NULL".)^ +** +** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory +** is available to hold the result, or if the result would exceed the +** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. +** +** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of +** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time +** option causes sqlite3_expanded_sql() to always return NULL. +** +** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) +** are managed by SQLite and are automatically freed when the prepared +** statement is finalized. +** ^The string returned by sqlite3_expanded_sql(P), on the other hand, +** is obtained from [sqlite3_malloc()] and must be freed by the application +** by passing it to [sqlite3_free()]. +** +** ^The sqlite3_normalized_sql() interface is only available if +** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. +*/ +SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); +SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); +#ifdef SQLITE_ENABLE_NORMALIZE +SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); +#endif + +/* +** CAPI3REF: Determine If An SQL Statement Writes The Database +** METHOD: sqlite3_stmt +** +** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if +** and only if the [prepared statement] X makes no direct changes to +** the content of the database file. +** +** Note that [application-defined SQL functions] or +** [virtual tables] might change the database indirectly as a side effect. +** ^(For example, if an application defines a function "eval()" that +** calls [sqlite3_exec()], then the following SQL statement would +** change the database file through side-effects: +** +** 

+**    SELECT eval('DELETE FROM t1') FROM t2;
+**
+** +** But because the [SELECT] statement does not change the database file +** directly, sqlite3_stmt_readonly() would still return true.)^ +** +** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], +** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, +** since the statements themselves do not actually modify the database but +** rather they control the timing of when other statements modify the +** database. ^The [ATTACH] and [DETACH] statements also cause +** sqlite3_stmt_readonly() to return true since, while those statements +** change the configuration of a database connection, they do not make +** changes to the content of the database files on disk. +** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since +** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and +** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so +** sqlite3_stmt_readonly() returns false for those commands. +** +** ^This routine returns false if there is any possibility that the +** statement might change the database file. ^A false return does +** not guarantee that the statement will change the database file. +** ^For example, an UPDATE statement might have a WHERE clause that +** makes it a no-op, but the sqlite3_stmt_readonly() result would still +** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a +** read-only no-op if the table already exists, but +** sqlite3_stmt_readonly() still returns false for such a statement. +** +** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN] +** statement, then sqlite3_stmt_readonly(X) returns the same value as +** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted. +*/ +SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); + +/* +** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement +** METHOD: sqlite3_stmt +** +** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the +** prepared statement S is an EXPLAIN statement, or 2 if the +** statement S is an EXPLAIN QUERY PLAN. +** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is +** an ordinary statement or a NULL pointer. +*/ +SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); + +/* +** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement +** METHOD: sqlite3_stmt +** +** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN +** setting for [prepared statement] S. If E is zero, then S becomes +** a normal prepared statement. If E is 1, then S behaves as if +** its SQL text began with "[EXPLAIN]". If E is 2, then S behaves as if +** its SQL text began with "[EXPLAIN QUERY PLAN]". +** +** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared. +** SQLite tries to avoid a reprepare, but a reprepare might be necessary +** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode. +** +** Because of the potential need to reprepare, a call to +** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be +** reprepared because it was created using [sqlite3_prepare()] instead of +** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and +** hence has no saved SQL text with which to reprepare. +** +** Changing the explain setting for a prepared statement does not change +** the original SQL text for the statement. Hence, if the SQL text originally +** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0) +** is called to convert the statement into an ordinary statement, the EXPLAIN +** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S) +** output, even though the statement now acts like a normal SQL statement. +** +** This routine returns SQLITE_OK if the explain mode is successfully +** changed, or an error code if the explain mode could not be changed. +** The explain mode cannot be changed while a statement is active. +** Hence, it is good practice to call [sqlite3_reset(S)] +** immediately prior to calling sqlite3_stmt_explain(S,E). +*/ +SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode); + +/* +** CAPI3REF: Determine If A Prepared Statement Has Been Reset +** METHOD: sqlite3_stmt +** +** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the +** [prepared statement] S has been stepped at least once using +** [sqlite3_step(S)] but has neither run to completion (returned +** [SQLITE_DONE] from [sqlite3_step(S)]) nor +** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) +** interface returns false if S is a NULL pointer. If S is not a +** NULL pointer and is not a pointer to a valid [prepared statement] +** object, then the behavior is undefined and probably undesirable. +** +** This interface can be used in combination [sqlite3_next_stmt()] +** to locate all prepared statements associated with a database +** connection that are in need of being reset. This can be used, +** for example, in diagnostic routines to search for prepared +** statements that are holding a transaction open. +*/ +SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); + +/* +** CAPI3REF: Dynamically Typed Value Object +** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} +** +** SQLite uses the sqlite3_value object to represent all values +** that can be stored in a database table. SQLite uses dynamic typing +** for the values it stores. ^Values stored in sqlite3_value objects +** can be integers, floating point values, strings, BLOBs, or NULL. +** +** An sqlite3_value object may be either "protected" or "unprotected". +** Some interfaces require a protected sqlite3_value. Other interfaces +** will accept either a protected or an unprotected sqlite3_value. +** Every interface that accepts sqlite3_value arguments specifies +** whether or not it requires a protected sqlite3_value. The +** [sqlite3_value_dup()] interface can be used to construct a new +** protected sqlite3_value from an unprotected sqlite3_value. +** +** The terms "protected" and "unprotected" refer to whether or not +** a mutex is held. An internal mutex is held for a protected +** sqlite3_value object but no mutex is held for an unprotected +** sqlite3_value object. If SQLite is compiled to be single-threaded +** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) +** or if SQLite is run in one of reduced mutex modes +** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] +** then there is no distinction between protected and unprotected +** sqlite3_value objects and they can be used interchangeably. However, +** for maximum code portability it is recommended that applications +** still make the distinction between protected and unprotected +** sqlite3_value objects even when not strictly required. +** +** ^The sqlite3_value objects that are passed as parameters into the +** implementation of [application-defined SQL functions] are protected. +** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()] +** are protected. +** ^The sqlite3_value object returned by +** [sqlite3_column_value()] is unprotected. +** Unprotected sqlite3_value objects may only be used as arguments +** to [sqlite3_result_value()], [sqlite3_bind_value()], and +** [sqlite3_value_dup()]. +** The [sqlite3_value_blob | sqlite3_value_type()] family of +** interfaces require protected sqlite3_value objects. +*/ +typedef struct sqlite3_value sqlite3_value; + +/* +** CAPI3REF: SQL Function Context Object +** +** The context in which an SQL function executes is stored in an +** sqlite3_context object. ^A pointer to an sqlite3_context object +** is always first parameter to [application-defined SQL functions]. +** The application-defined SQL function implementation will pass this +** pointer through into calls to [sqlite3_result_int | sqlite3_result()], +** [sqlite3_aggregate_context()], [sqlite3_user_data()], +** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], +** and/or [sqlite3_set_auxdata()]. +*/ +typedef struct sqlite3_context sqlite3_context; + +/* +** CAPI3REF: Binding Values To Prepared Statements +** KEYWORDS: {host parameter} {host parameters} {host parameter name} +** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} +** METHOD: sqlite3_stmt +** +** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, +** literals may be replaced by a [parameter] that matches one of following +** templates: +** +**
    +**
  • ? +**
  • ?NNN +**
  • :VVV +**
  • @VVV +**
  • $VVV +**
+** +** In the templates above, NNN represents an integer literal, +** and VVV represents an alphanumeric identifier.)^ ^The values of these +** parameters (also called "host parameter names" or "SQL parameters") +** can be set using the sqlite3_bind_*() routines defined here. +** +** ^The first argument to the sqlite3_bind_*() routines is always +** a pointer to the [sqlite3_stmt] object returned from +** [sqlite3_prepare_v2()] or its variants. +** +** ^The second argument is the index of the SQL parameter to be set. +** ^The leftmost SQL parameter has an index of 1. ^When the same named +** SQL parameter is used more than once, second and subsequent +** occurrences have the same index as the first occurrence. +** ^The index for named parameters can be looked up using the +** [sqlite3_bind_parameter_index()] API if desired. ^The index +** for "?NNN" parameters is the value of NNN. +** ^The NNN value must be between 1 and the [sqlite3_limit()] +** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). +** +** ^The third argument is the value to bind to the parameter. +** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() +** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter +** is ignored and the end result is the same as sqlite3_bind_null(). +** ^If the third parameter to sqlite3_bind_text() is not NULL, then +** it should be a pointer to well-formed UTF8 text. +** ^If the third parameter to sqlite3_bind_text16() is not NULL, then +** it should be a pointer to well-formed UTF16 text. +** ^If the third parameter to sqlite3_bind_text64() is not NULL, then +** it should be a pointer to a well-formed unicode string that is +** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 +** otherwise. +** +** [[byte-order determination rules]] ^The byte-order of +** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) +** found in first character, which is removed, or in the absence of a BOM +** the byte order is the native byte order of the host +** machine for sqlite3_bind_text16() or the byte order specified in +** the 6th parameter for sqlite3_bind_text64().)^ +** ^If UTF16 input text contains invalid unicode +** characters, then SQLite might change those invalid characters +** into the unicode replacement character: U+FFFD. +** +** ^(In those routines that have a fourth argument, its value is the +** number of bytes in the parameter. To be clear: the value is the +** number of bytes in the value, not the number of characters.)^ +** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() +** is negative, then the length of the string is +** the number of bytes up to the first zero terminator. +** If the fourth parameter to sqlite3_bind_blob() is negative, then +** the behavior is undefined. +** If a non-negative fourth parameter is provided to sqlite3_bind_text() +** or sqlite3_bind_text16() or sqlite3_bind_text64() then +** that parameter must be the byte offset +** where the NUL terminator would occur assuming the string were NUL +** terminated. If any NUL characters occurs at byte offsets less than +** the value of the fourth parameter then the resulting string value will +** contain embedded NULs. The result of expressions involving strings +** with embedded NULs is undefined. +** +** ^The fifth argument to the BLOB and string binding interfaces controls +** or indicates the lifetime of the object referenced by the third parameter. +** These three options exist: +** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished +** with it may be passed. ^It is called to dispose of the BLOB or string even +** if the call to the bind API fails, except the destructor is not called if +** the third parameter is a NULL pointer or the fourth parameter is negative. +** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that +** the application remains responsible for disposing of the object. ^In this +** case, the object and the provided pointer to it must remain valid until +** either the prepared statement is finalized or the same SQL parameter is +** bound to something else, whichever occurs sooner. +** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the +** object is to be copied prior to the return from sqlite3_bind_*(). ^The +** object and pointer to it must remain valid until then. ^SQLite will then +** manage the lifetime of its private copy. +** +** ^The sixth argument to sqlite3_bind_text64() must be one of +** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] +** to specify the encoding of the text in the third parameter. If +** the sixth argument to sqlite3_bind_text64() is not one of the +** allowed values shown above, or if the text encoding is different +** from the encoding specified by the sixth parameter, then the behavior +** is undefined. +** +** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that +** is filled with zeroes. ^A zeroblob uses a fixed amount of memory +** (just an integer to hold its size) while it is being processed. +** Zeroblobs are intended to serve as placeholders for BLOBs whose +** content is later written using +** [sqlite3_blob_open | incremental BLOB I/O] routines. +** ^A negative value for the zeroblob results in a zero-length BLOB. +** +** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in +** [prepared statement] S to have an SQL value of NULL, but to also be +** associated with the pointer P of type T. ^D is either a NULL pointer or +** a pointer to a destructor function for P. ^SQLite will invoke the +** destructor D with a single argument of P when it is finished using +** P. The T parameter should be a static string, preferably a string +** literal. The sqlite3_bind_pointer() routine is part of the +** [pointer passing interface] added for SQLite 3.20.0. +** +** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer +** for the [prepared statement] or with a prepared statement for which +** [sqlite3_step()] has been called more recently than [sqlite3_reset()], +** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() +** routine is passed a [prepared statement] that has been finalized, the +** result is undefined and probably harmful. +** +** ^Bindings are not cleared by the [sqlite3_reset()] routine. +** ^Unbound parameters are interpreted as NULL. +** +** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an +** [error code] if anything goes wrong. +** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB +** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or +** [SQLITE_MAX_LENGTH]. +** ^[SQLITE_RANGE] is returned if the parameter +** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. +** +** See also: [sqlite3_bind_parameter_count()], +** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. +*/ +SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); +SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, + void(*)(void*)); +SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); +SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); +SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); +SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); +SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); +SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); +SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, + void(*)(void*), unsigned char encoding); +SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); +SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); +SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); +SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); + +/* +** CAPI3REF: Number Of SQL Parameters +** METHOD: sqlite3_stmt +** +** ^This routine can be used to find the number of [SQL parameters] +** in a [prepared statement]. SQL parameters are tokens of the +** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as +** placeholders for values that are [sqlite3_bind_blob | bound] +** to the parameters at a later time. +** +** ^(This routine actually returns the index of the largest (rightmost) +** parameter. For all forms except ?NNN, this will correspond to the +** number of unique parameters. If parameters of the ?NNN form are used, +** there may be gaps in the list.)^ +** +** See also: [sqlite3_bind_blob|sqlite3_bind()], +** [sqlite3_bind_parameter_name()], and +** [sqlite3_bind_parameter_index()]. +*/ +SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); + +/* +** CAPI3REF: Name Of A Host Parameter +** METHOD: sqlite3_stmt +** +** ^The sqlite3_bind_parameter_name(P,N) interface returns +** the name of the N-th [SQL parameter] in the [prepared statement] P. +** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" +** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" +** respectively. +** In other words, the initial ":" or "$" or "@" or "?" +** is included as part of the name.)^ +** ^Parameters of the form "?" without a following integer have no name +** and are referred to as "nameless" or "anonymous parameters". +** +** ^The first host parameter has an index of 1, not 0. +** +** ^If the value N is out of range or if the N-th parameter is +** nameless, then NULL is returned. ^The returned string is +** always in UTF-8 encoding even if the named parameter was +** originally specified as UTF-16 in [sqlite3_prepare16()], +** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. +** +** See also: [sqlite3_bind_blob|sqlite3_bind()], +** [sqlite3_bind_parameter_count()], and +** [sqlite3_bind_parameter_index()]. +*/ +SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); + +/* +** CAPI3REF: Index Of A Parameter With A Given Name +** METHOD: sqlite3_stmt +** +** ^Return the index of an SQL parameter given its name. ^The +** index value returned is suitable for use as the second +** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero +** is returned if no matching parameter is found. ^The parameter +** name must be given in UTF-8 even if the original statement +** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or +** [sqlite3_prepare16_v3()]. +** +** See also: [sqlite3_bind_blob|sqlite3_bind()], +** [sqlite3_bind_parameter_count()], and +** [sqlite3_bind_parameter_name()]. +*/ +SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); + +/* +** CAPI3REF: Reset All Bindings On A Prepared Statement +** METHOD: sqlite3_stmt +** +** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset +** the [sqlite3_bind_blob | bindings] on a [prepared statement]. +** ^Use this routine to reset all host parameters to NULL. +*/ +SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); + +/* +** CAPI3REF: Number Of Columns In A Result Set +** METHOD: sqlite3_stmt +** +** ^Return the number of columns in the result set returned by the +** [prepared statement]. ^If this routine returns 0, that means the +** [prepared statement] returns no data (for example an [UPDATE]). +** ^However, just because this routine returns a positive number does not +** mean that one or more rows of data will be returned. ^A SELECT statement +** will always have a positive sqlite3_column_count() but depending on the +** WHERE clause constraints and the table content, it might return no rows. +** +** See also: [sqlite3_data_count()] +*/ +SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); + +/* +** CAPI3REF: Column Names In A Result Set +** METHOD: sqlite3_stmt +** +** ^These routines return the name assigned to a particular column +** in the result set of a [SELECT] statement. ^The sqlite3_column_name() +** interface returns a pointer to a zero-terminated UTF-8 string +** and sqlite3_column_name16() returns a pointer to a zero-terminated +** UTF-16 string. ^The first parameter is the [prepared statement] +** that implements the [SELECT] statement. ^The second parameter is the +** column number. ^The leftmost column is number 0. +** +** ^The returned string pointer is valid until either the [prepared statement] +** is destroyed by [sqlite3_finalize()] or until the statement is automatically +** reprepared by the first call to [sqlite3_step()] for a particular run +** or until the next call to +** sqlite3_column_name() or sqlite3_column_name16() on the same column. +** +** ^If sqlite3_malloc() fails during the processing of either routine +** (for example during a conversion from UTF-8 to UTF-16) then a +** NULL pointer is returned. +** +** ^The name of a result column is the value of the "AS" clause for +** that column, if there is an AS clause. If there is no AS clause +** then the name of the column is unspecified and may change from +** one release of SQLite to the next. +*/ +SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); +SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); + +/* +** CAPI3REF: Source Of Data In A Query Result +** METHOD: sqlite3_stmt +** +** ^These routines provide a means to determine the database, table, and +** table column that is the origin of a particular result column in +** [SELECT] statement. +** ^The name of the database or table or column can be returned as +** either a UTF-8 or UTF-16 string. ^The _database_ routines return +** the database name, the _table_ routines return the table name, and +** the origin_ routines return the column name. +** ^The returned string is valid until the [prepared statement] is destroyed +** using [sqlite3_finalize()] or until the statement is automatically +** reprepared by the first call to [sqlite3_step()] for a particular run +** or until the same information is requested +** again in a different encoding. +** +** ^The names returned are the original un-aliased names of the +** database, table, and column. +** +** ^The first argument to these interfaces is a [prepared statement]. +** ^These functions return information about the Nth result column returned by +** the statement, where N is the second function argument. +** ^The left-most column is column 0 for these routines. +** +** ^If the Nth column returned by the statement is an expression or +** subquery and is not a column value, then all of these functions return +** NULL. ^These routines might also return NULL if a memory allocation error +** occurs. ^Otherwise, they return the name of the attached database, table, +** or column that query result column was extracted from. +** +** ^As with all other SQLite APIs, those whose names end with "16" return +** UTF-16 encoded strings and the other functions return UTF-8. +** +** ^These APIs are only available if the library was compiled with the +** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. +** +** If two or more threads call one or more +** [sqlite3_column_database_name | column metadata interfaces] +** for the same [prepared statement] and result column +** at the same time then the results are undefined. +*/ +SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); +SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); +SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); +SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); +SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); +SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); + +/* +** CAPI3REF: Declared Datatype Of A Query Result +** METHOD: sqlite3_stmt +** +** ^(The first parameter is a [prepared statement]. +** If this statement is a [SELECT] statement and the Nth column of the +** returned result set of that [SELECT] is a table column (not an +** expression or subquery) then the declared type of the table +** column is returned.)^ ^If the Nth column of the result set is an +** expression or subquery, then a NULL pointer is returned. +** ^The returned string is always UTF-8 encoded. +** +** ^(For example, given the database schema: +** +** CREATE TABLE t1(c1 VARIANT); +** +** and the following statement to be compiled: +** +** SELECT c1 + 1, c1 FROM t1; +** +** this routine would return the string "VARIANT" for the second result +** column (i==1), and a NULL pointer for the first result column (i==0).)^ +** +** ^SQLite uses dynamic run-time typing. ^So just because a column +** is declared to contain a particular type does not mean that the +** data stored in that column is of the declared type. SQLite is +** strongly typed, but the typing is dynamic not static. ^Type +** is associated with individual values, not with the containers +** used to hold those values. +*/ +SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); +SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); + +/* +** CAPI3REF: Evaluate An SQL Statement +** METHOD: sqlite3_stmt +** +** After a [prepared statement] has been prepared using any of +** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], +** or [sqlite3_prepare16_v3()] or one of the legacy +** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function +** must be called one or more times to evaluate the statement. +** +** The details of the behavior of the sqlite3_step() interface depend +** on whether the statement was prepared using the newer "vX" interfaces +** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], +** [sqlite3_prepare16_v2()] or the older legacy +** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the +** new "vX" interface is recommended for new applications but the legacy +** interface will continue to be supported. +** +** ^In the legacy interface, the return value will be either [SQLITE_BUSY], +** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. +** ^With the "v2" interface, any of the other [result codes] or +** [extended result codes] might be returned as well. +** +** ^[SQLITE_BUSY] means that the database engine was unable to acquire the +** database locks it needs to do its job. ^If the statement is a [COMMIT] +** or occurs outside of an explicit transaction, then you can retry the +** statement. If the statement is not a [COMMIT] and occurs within an +** explicit transaction then you should rollback the transaction before +** continuing. +** +** ^[SQLITE_DONE] means that the statement has finished executing +** successfully. sqlite3_step() should not be called again on this virtual +** machine without first calling [sqlite3_reset()] to reset the virtual +** machine back to its initial state. +** +** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] +** is returned each time a new row of data is ready for processing by the +** caller. The values may be accessed using the [column access functions]. +** sqlite3_step() is called again to retrieve the next row of data. +** +** ^[SQLITE_ERROR] means that a run-time error (such as a constraint +** violation) has occurred. sqlite3_step() should not be called again on +** the VM. More information may be found by calling [sqlite3_errmsg()]. +** ^With the legacy interface, a more specific error code (for example, +** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) +** can be obtained by calling [sqlite3_reset()] on the +** [prepared statement]. ^In the "v2" interface, +** the more specific error code is returned directly by sqlite3_step(). +** +** [SQLITE_MISUSE] means that the this routine was called inappropriately. +** Perhaps it was called on a [prepared statement] that has +** already been [sqlite3_finalize | finalized] or on one that had +** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could +** be the case that the same database connection is being used by two or +** more threads at the same moment in time. +** +** For all versions of SQLite up to and including 3.6.23.1, a call to +** [sqlite3_reset()] was required after sqlite3_step() returned anything +** other than [SQLITE_ROW] before any subsequent invocation of +** sqlite3_step(). Failure to reset the prepared statement using +** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from +** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], +** sqlite3_step() began +** calling [sqlite3_reset()] automatically in this circumstance rather +** than returning [SQLITE_MISUSE]. This is not considered a compatibility +** break because any application that ever receives an SQLITE_MISUSE error +** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option +** can be used to restore the legacy behavior. +** +** Goofy Interface Alert: In the legacy interface, the sqlite3_step() +** API always returns a generic error code, [SQLITE_ERROR], following any +** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call +** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the +** specific [error codes] that better describes the error. +** We admit that this is a goofy design. The problem has been fixed +** with the "v2" interface. If you prepare all of your SQL statements +** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] +** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead +** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, +** then the more specific [error codes] are returned directly +** by sqlite3_step(). The use of the "vX" interfaces is recommended. +*/ +SQLITE_API int sqlite3_step(sqlite3_stmt*); + +/* +** CAPI3REF: Number of columns in a result set +** METHOD: sqlite3_stmt +** +** ^The sqlite3_data_count(P) interface returns the number of columns in the +** current row of the result set of [prepared statement] P. +** ^If prepared statement P does not have results ready to return +** (via calls to the [sqlite3_column_int | sqlite3_column()] family of +** interfaces) then sqlite3_data_count(P) returns 0. +** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. +** ^The sqlite3_data_count(P) routine returns 0 if the previous call to +** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) +** will return non-zero if previous call to [sqlite3_step](P) returned +** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] +** where it always returns zero since each step of that multi-step +** pragma returns 0 columns of data. +** +** See also: [sqlite3_column_count()] +*/ +SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); + +/* +** CAPI3REF: Fundamental Datatypes +** KEYWORDS: SQLITE_TEXT +** +** ^(Every value in SQLite has one of five fundamental datatypes: +** +**
    +**
  • 64-bit signed integer +**
  • 64-bit IEEE floating point number +**
  • string +**
  • BLOB +**
  • NULL +**
)^ +** +** These constants are codes for each of those types. +** +** Note that the SQLITE_TEXT constant was also used in SQLite version 2 +** for a completely different meaning. Software that links against both +** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not +** SQLITE_TEXT. +*/ +#define SQLITE_INTEGER 1 +#define SQLITE_FLOAT 2 +#define SQLITE_BLOB 4 +#define SQLITE_NULL 5 +#ifdef SQLITE_TEXT +# undef SQLITE_TEXT +#else +# define SQLITE_TEXT 3 +#endif +#define SQLITE3_TEXT 3 + +/* +** CAPI3REF: Result Values From A Query +** KEYWORDS: {column access functions} +** METHOD: sqlite3_stmt +** +** Summary: +**
+**
sqlite3_column_blob→BLOB result +**
sqlite3_column_double→REAL result +**
sqlite3_column_int→32-bit INTEGER result +**
sqlite3_column_int64→64-bit INTEGER result +**
sqlite3_column_text→UTF-8 TEXT result +**
sqlite3_column_text16→UTF-16 TEXT result +**
sqlite3_column_value→The result as an +** [sqlite3_value|unprotected sqlite3_value] object. +**
    +**
sqlite3_column_bytes→Size of a BLOB +** or a UTF-8 TEXT result in bytes +**
sqlite3_column_bytes16   +** →  Size of UTF-16 +** TEXT in bytes +**
sqlite3_column_type→Default +** datatype of the result +**
+** +** Details: +** +** ^These routines return information about a single column of the current +** result row of a query. ^In every case the first argument is a pointer +** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] +** that was returned from [sqlite3_prepare_v2()] or one of its variants) +** and the second argument is the index of the column for which information +** should be returned. ^The leftmost column of the result set has the index 0. +** ^The number of columns in the result can be determined using +** [sqlite3_column_count()]. +** +** If the SQL statement does not currently point to a valid row, or if the +** column index is out of range, the result is undefined. +** These routines may only be called when the most recent call to +** [sqlite3_step()] has returned [SQLITE_ROW] and neither +** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. +** If any of these routines are called after [sqlite3_reset()] or +** [sqlite3_finalize()] or after [sqlite3_step()] has returned +** something other than [SQLITE_ROW], the results are undefined. +** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] +** are called from a different thread while any of these routines +** are pending, then the results are undefined. +** +** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) +** each return the value of a result column in a specific data format. If +** the result column is not initially in the requested format (for example, +** if the query returns an integer but the sqlite3_column_text() interface +** is used to extract the value) then an automatic type conversion is performed. +** +** ^The sqlite3_column_type() routine returns the +** [SQLITE_INTEGER | datatype code] for the initial data type +** of the result column. ^The returned value is one of [SQLITE_INTEGER], +** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. +** The return value of sqlite3_column_type() can be used to decide which +** of the first six interface should be used to extract the column value. +** The value returned by sqlite3_column_type() is only meaningful if no +** automatic type conversions have occurred for the value in question. +** After a type conversion, the result of calling sqlite3_column_type() +** is undefined, though harmless. Future +** versions of SQLite may change the behavior of sqlite3_column_type() +** following a type conversion. +** +** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() +** or sqlite3_column_bytes16() interfaces can be used to determine the size +** of that BLOB or string. +** +** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() +** routine returns the number of bytes in that BLOB or string. +** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts +** the string to UTF-8 and then returns the number of bytes. +** ^If the result is a numeric value then sqlite3_column_bytes() uses +** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns +** the number of bytes in that string. +** ^If the result is NULL, then sqlite3_column_bytes() returns zero. +** +** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() +** routine returns the number of bytes in that BLOB or string. +** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts +** the string to UTF-16 and then returns the number of bytes. +** ^If the result is a numeric value then sqlite3_column_bytes16() uses +** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns +** the number of bytes in that string. +** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. +** +** ^The values returned by [sqlite3_column_bytes()] and +** [sqlite3_column_bytes16()] do not include the zero terminators at the end +** of the string. ^For clarity: the values returned by +** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of +** bytes in the string, not the number of characters. +** +** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), +** even empty strings, are always zero-terminated. ^The return +** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. +** +** ^Strings returned by sqlite3_column_text16() always have the endianness +** which is native to the platform, regardless of the text encoding set +** for the database. +** +** Warning: ^The object returned by [sqlite3_column_value()] is an +** [unprotected sqlite3_value] object. In a multithreaded environment, +** an unprotected sqlite3_value object may only be used safely with +** [sqlite3_bind_value()] and [sqlite3_result_value()]. +** If the [unprotected sqlite3_value] object returned by +** [sqlite3_column_value()] is used in any other way, including calls +** to routines like [sqlite3_value_int()], [sqlite3_value_text()], +** or [sqlite3_value_bytes()], the behavior is not threadsafe. +** Hence, the sqlite3_column_value() interface +** is normally only useful within the implementation of +** [application-defined SQL functions] or [virtual tables], not within +** top-level application code. +** +** These routines may attempt to convert the datatype of the result. +** ^For example, if the internal representation is FLOAT and a text result +** is requested, [sqlite3_snprintf()] is used internally to perform the +** conversion automatically. ^(The following table details the conversions +** that are applied: +** +**
+** +**
Internal
Type 		Requested
Type 		Conversion +** +**
NULL INTEGER Result is 0 +**
NULL FLOAT Result is 0.0 +**
NULL TEXT Result is a NULL pointer +**
NULL BLOB Result is a NULL pointer +**
INTEGER FLOAT Convert from integer to float +**
INTEGER TEXT ASCII rendering of the integer +**
INTEGER BLOB Same as INTEGER->TEXT +**
FLOAT INTEGER [CAST] to INTEGER +**
FLOAT TEXT ASCII rendering of the float +**
FLOAT BLOB [CAST] to BLOB +**
TEXT INTEGER [CAST] to INTEGER +**
TEXT FLOAT [CAST] to REAL +**
TEXT BLOB No change +**
BLOB INTEGER [CAST] to INTEGER +**
BLOB FLOAT [CAST] to REAL +**
BLOB TEXT [CAST] to TEXT, ensure zero terminator +**
+**
)^ +** +** Note that when type conversions occur, pointers returned by prior +** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or +** sqlite3_column_text16() may be invalidated. +** Type conversions and pointer invalidations might occur +** in the following cases: +** +**
    +**
  • The initial content is a BLOB and sqlite3_column_text() or +** sqlite3_column_text16() is called. A zero-terminator might +** need to be added to the string.
    • +**
  • The initial content is UTF-8 text and sqlite3_column_bytes16() or +** sqlite3_column_text16() is called. The content must be converted +** to UTF-16.
    • +**
  • The initial content is UTF-16 text and sqlite3_column_bytes() or +** sqlite3_column_text() is called. The content must be converted +** to UTF-8.
    • +**
+** +** ^Conversions between UTF-16be and UTF-16le are always done in place and do +** not invalidate a prior pointer, though of course the content of the buffer +** that the prior pointer references will have been modified. Other kinds +** of conversion are done in place when it is possible, but sometimes they +** are not possible and in those cases prior pointers are invalidated. +** +** The safest policy is to invoke these routines +** in one of the following ways: +** +**
    +**
  • sqlite3_column_text() followed by sqlite3_column_bytes()
    • +**
  • sqlite3_column_blob() followed by sqlite3_column_bytes()
    • +**
  • sqlite3_column_text16() followed by sqlite3_column_bytes16()
    • +**
+** +** In other words, you should call sqlite3_column_text(), +** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result +** into the desired format, then invoke sqlite3_column_bytes() or +** sqlite3_column_bytes16() to find the size of the result. Do not mix calls +** to sqlite3_column_text() or sqlite3_column_blob() with calls to +** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() +** with calls to sqlite3_column_bytes(). +** +** ^The pointers returned are valid until a type conversion occurs as +** described above, or until [sqlite3_step()] or [sqlite3_reset()] or +** [sqlite3_finalize()] is called. ^The memory space used to hold strings +** and BLOBs is freed automatically. Do not pass the pointers returned +** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into +** [sqlite3_free()]. +** +** As long as the input parameters are correct, these routines will only +** fail if an out-of-memory error occurs during a format conversion. +** Only the following subset of interfaces are subject to out-of-memory +** errors: +** +**
    +**
  • sqlite3_column_blob() +**
  • sqlite3_column_text() +**
  • sqlite3_column_text16() +**
  • sqlite3_column_bytes() +**
  • sqlite3_column_bytes16() +**
+** +** If an out-of-memory error occurs, then the return value from these +** routines is the same as if the column had contained an SQL NULL value. +** Valid SQL NULL returns can be distinguished from out-of-memory errors +** by invoking the [sqlite3_errcode()] immediately after the suspect +** return value is obtained and before any +** other SQLite interface is called on the same [database connection]. +*/ +SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); +SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); +SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); +SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); +SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); +SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); +SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); +SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); +SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); +SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); + +/* +** CAPI3REF: Destroy A Prepared Statement Object +** DESTRUCTOR: sqlite3_stmt +** +** ^The sqlite3_finalize() function is called to delete a [prepared statement]. +** ^If the most recent evaluation of the statement encountered no errors +** or if the statement is never been evaluated, then sqlite3_finalize() returns +** SQLITE_OK. ^If the most recent evaluation of statement S failed, then +** sqlite3_finalize(S) returns the appropriate [error code] or +** [extended error code]. +** +** ^The sqlite3_finalize(S) routine can be called at any point during +** the life cycle of [prepared statement] S: +** before statement S is ever evaluated, after +** one or more calls to [sqlite3_reset()], or after any call +** to [sqlite3_step()] regardless of whether or not the statement has +** completed execution. +** +** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. +** +** The application must finalize every [prepared statement] in order to avoid +** resource leaks. It is a grievous error for the application to try to use +** a prepared statement after it has been finalized. Any use of a prepared +** statement after it has been finalized can result in undefined and +** undesirable behavior such as segfaults and heap corruption. +*/ +SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); + +/* +** CAPI3REF: Reset A Prepared Statement Object +** METHOD: sqlite3_stmt +** +** The sqlite3_reset() function is called to reset a [prepared statement] +** object back to its initial state, ready to be re-executed. +** ^Any SQL statement variables that had values bound to them using +** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. +** Use [sqlite3_clear_bindings()] to reset the bindings. +** +** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S +** back to the beginning of its program. +** +** ^The return code from [sqlite3_reset(S)] indicates whether or not +** the previous evaluation of prepared statement S completed successfully. +** ^If [sqlite3_step(S)] has never before been called on S or if +** [sqlite3_step(S)] has not been called since the previous call +** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return +** [SQLITE_OK]. +** +** ^If the most recent call to [sqlite3_step(S)] for the +** [prepared statement] S indicated an error, then +** [sqlite3_reset(S)] returns an appropriate [error code]. +** ^The [sqlite3_reset(S)] interface might also return an [error code] +** if there were no prior errors but the process of resetting +** the prepared statement caused a new error. ^For example, if an +** [INSERT] statement with a [RETURNING] clause is only stepped one time, +** that one call to [sqlite3_step(S)] might return SQLITE_ROW but +** the overall statement might still fail and the [sqlite3_reset(S)] call +** might return SQLITE_BUSY if locking constraints prevent the +** database change from committing. Therefore, it is important that +** applications check the return code from [sqlite3_reset(S)] even if +** no prior call to [sqlite3_step(S)] indicated a problem. +** +** ^The [sqlite3_reset(S)] interface does not change the values +** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. +*/ +SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); + + +/* +** CAPI3REF: Create Or Redefine SQL Functions +** KEYWORDS: {function creation routines} +** METHOD: sqlite3 +** +** ^These functions (collectively known as "function creation routines") +** are used to add SQL functions or aggregates or to redefine the behavior +** of existing SQL functions or aggregates. The only differences between +** the three "sqlite3_create_function*" routines are the text encoding +** expected for the second parameter (the name of the function being +** created) and the presence or absence of a destructor callback for +** the application data pointer. Function sqlite3_create_window_function() +** is similar, but allows the user to supply the extra callback functions +** needed by [aggregate window functions]. +** +** ^The first parameter is the [database connection] to which the SQL +** function is to be added. ^If an application uses more than one database +** connection then application-defined SQL functions must be added +** to each database connection separately. +** +** ^The second parameter is the name of the SQL function to be created or +** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 +** representation, exclusive of the zero-terminator. ^Note that the name +** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. +** ^Any attempt to create a function with a longer name +** will result in [SQLITE_MISUSE] being returned. +** +** ^The third parameter (nArg) +** is the number of arguments that the SQL function or +** aggregate takes. ^If this parameter is -1, then the SQL function or +** aggregate may take any number of arguments between 0 and the limit +** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third +** parameter is less than -1 or greater than 127 then the behavior is +** undefined. +** +** ^The fourth parameter, eTextRep, specifies what +** [SQLITE_UTF8 | text encoding] this SQL function prefers for +** its parameters. The application should set this parameter to +** [SQLITE_UTF16LE] if the function implementation invokes +** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the +** implementation invokes [sqlite3_value_text16be()] on an input, or +** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] +** otherwise. ^The same SQL function may be registered multiple times using +** different preferred text encodings, with different implementations for +** each encoding. +** ^When multiple implementations of the same function are available, SQLite +** will pick the one that involves the least amount of data conversion. +** +** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] +** to signal that the function will always return the same result given +** the same inputs within a single SQL statement. Most SQL functions are +** deterministic. The built-in [random()] SQL function is an example of a +** function that is not deterministic. The SQLite query planner is able to +** perform additional optimizations on deterministic functions, so use +** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. +** +** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] +** flag, which if present prevents the function from being invoked from +** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, +** index expressions, or the WHERE clause of partial indexes. +** +** For best security, the [SQLITE_DIRECTONLY] flag is recommended for +** all application-defined SQL functions that do not need to be +** used inside of triggers, view, CHECK constraints, or other elements of +** the database schema. This flags is especially recommended for SQL +** functions that have side effects or reveal internal application state. +** Without this flag, an attacker might be able to modify the schema of +** a database file to include invocations of the function with parameters +** chosen by the attacker, which the application will then execute when +** the database file is opened and read. +** +** ^(The fifth parameter is an arbitrary pointer. The implementation of the +** function can gain access to this pointer using [sqlite3_user_data()].)^ +** +** ^The sixth, seventh and eighth parameters passed to the three +** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are +** pointers to C-language functions that implement the SQL function or +** aggregate. ^A scalar SQL function requires an implementation of the xFunc +** callback only; NULL pointers must be passed as the xStep and xFinal +** parameters. ^An aggregate SQL function requires an implementation of xStep +** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing +** SQL function or aggregate, pass NULL pointers for all three function +** callbacks. +** +** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue +** and xInverse) passed to sqlite3_create_window_function are pointers to +** C-language callbacks that implement the new function. xStep and xFinal +** must both be non-NULL. xValue and xInverse may either both be NULL, in +** which case a regular aggregate function is created, or must both be +** non-NULL, in which case the new function may be used as either an aggregate +** or aggregate window function. More details regarding the implementation +** of aggregate window functions are +** [user-defined window functions|available here]. +** +** ^(If the final parameter to sqlite3_create_function_v2() or +** sqlite3_create_window_function() is not NULL, then it is destructor for +** the application data pointer. The destructor is invoked when the function +** is deleted, either by being overloaded or when the database connection +** closes.)^ ^The destructor is also invoked if the call to +** sqlite3_create_function_v2() fails. ^When the destructor callback is +** invoked, it is passed a single argument which is a copy of the application +** data pointer which was the fifth parameter to sqlite3_create_function_v2(). +** +** ^It is permitted to register multiple implementations of the same +** functions with the same name but with either differing numbers of +** arguments or differing preferred text encodings. ^SQLite will use +** the implementation that most closely matches the way in which the +** SQL function is used. ^A function implementation with a non-negative +** nArg parameter is a better match than a function implementation with +** a negative nArg. ^A function where the preferred text encoding +** matches the database encoding is a better +** match than a function where the encoding is different. +** ^A function where the encoding difference is between UTF16le and UTF16be +** is a closer match than a function where the encoding difference is +** between UTF8 and UTF16. +** +** ^Built-in functions may be overloaded by new application-defined functions. +** +** ^An application-defined function is permitted to call other +** SQLite interfaces. However, such calls must not +** close the database connection nor finalize or reset the prepared +** statement in which the function is running. +*/ +SQLITE_API int sqlite3_create_function( + sqlite3 *db, + const char *zFunctionName, + int nArg, + int eTextRep, + void *pApp, + void (*xFunc)(sqlite3_context*,int,sqlite3_value**), + void (*xStep)(sqlite3_context*,int,sqlite3_value**), + void (*xFinal)(sqlite3_context*) +); +SQLITE_API int sqlite3_create_function16( + sqlite3 *db, + const void *zFunctionName, + int nArg, + int eTextRep, + void *pApp, + void (*xFunc)(sqlite3_context*,int,sqlite3_value**), + void (*xStep)(sqlite3_context*,int,sqlite3_value**), + void (*xFinal)(sqlite3_context*) +); +SQLITE_API int sqlite3_create_function_v2( + sqlite3 *db, + const char *zFunctionName, + int nArg, + int eTextRep, + void *pApp, + void (*xFunc)(sqlite3_context*,int,sqlite3_value**), + void (*xStep)(sqlite3_context*,int,sqlite3_value**), + void (*xFinal)(sqlite3_context*), + void(*xDestroy)(void*) +); +SQLITE_API int sqlite3_create_window_function( + sqlite3 *db, + const char *zFunctionName, + int nArg, + int eTextRep, + void *pApp, + void (*xStep)(sqlite3_context*,int,sqlite3_value**), + void (*xFinal)(sqlite3_context*), + void (*xValue)(sqlite3_context*), + void (*xInverse)(sqlite3_context*,int,sqlite3_value**), + void(*xDestroy)(void*) +); + +/* +** CAPI3REF: Text Encodings +** +** These constant define integer codes that represent the various +** text encodings supported by SQLite. +*/ +#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ +#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ +#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ +#define SQLITE_UTF16 4 /* Use native byte order */ +#define SQLITE_ANY 5 /* Deprecated */ +#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ + +/* +** CAPI3REF: Function Flags +** +** These constants may be ORed together with the +** [SQLITE_UTF8 | preferred text encoding] as the fourth argument +** to [sqlite3_create_function()], [sqlite3_create_function16()], or +** [sqlite3_create_function_v2()]. +** +**
+** [[SQLITE_DETERMINISTIC]]
SQLITE_DETERMINISTIC
+** The SQLITE_DETERMINISTIC flag means that the new function always gives +** the same output when the input parameters are the same. +** The [abs|abs() function] is deterministic, for example, but +** [randomblob|randomblob()] is not. Functions must +** be deterministic in order to be used in certain contexts such as +** with the WHERE clause of [partial indexes] or in [generated columns]. +** SQLite might also optimize deterministic functions by factoring them +** out of inner loops. +**
+** +** [[SQLITE_DIRECTONLY]]
SQLITE_DIRECTONLY
+** The SQLITE_DIRECTONLY flag means that the function may only be invoked +** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in +** schema structures such as [CHECK constraints], [DEFAULT clauses], +** [expression indexes], [partial indexes], or [generated columns]. +**

+** The SQLITE_DIRECTONLY flag is recommended for any +** [application-defined SQL function] +** that has side-effects or that could potentially leak sensitive information. +** This will prevent attacks in which an application is tricked +** into using a database file that has had its schema surreptitiously +** modified to invoke the application-defined function in ways that are +** harmful. +**

+** Some people say it is good practice to set SQLITE_DIRECTONLY on all +** [application-defined SQL functions], regardless of whether or not they +** are security sensitive, as doing so prevents those functions from being used +** inside of the database schema, and thus ensures that the database +** can be inspected and modified using generic tools (such as the [CLI]) +** that do not have access to the application-defined functions. +**

+** +** [[SQLITE_INNOCUOUS]]
SQLITE_INNOCUOUS
+** The SQLITE_INNOCUOUS flag means that the function is unlikely +** to cause problems even if misused. An innocuous function should have +** no side effects and should not depend on any values other than its +** input parameters. The [abs|abs() function] is an example of an +** innocuous function. +** The [load_extension() SQL function] is not innocuous because of its +** side effects. +**

SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not +** exactly the same. The [random|random() function] is an example of a +** function that is innocuous but not deterministic. +**

Some heightened security settings +** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) +** disable the use of SQL functions inside views and triggers and in +** schema structures such as [CHECK constraints], [DEFAULT clauses], +** [expression indexes], [partial indexes], and [generated columns] unless +** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions +** are innocuous. Developers are advised to avoid using the +** SQLITE_INNOCUOUS flag for application-defined functions unless the +** function has been carefully audited and found to be free of potentially +** security-adverse side-effects and information-leaks. +**

+** +** [[SQLITE_SUBTYPE]]
SQLITE_SUBTYPE
+** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call +** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. +** This flag instructs SQLite to omit some corner-case optimizations that +** might disrupt the operation of the [sqlite3_value_subtype()] function, +** causing it to return zero rather than the correct subtype(). +** SQL functions that invokes [sqlite3_value_subtype()] should have this +** property. If the SQLITE_SUBTYPE property is omitted, then the return +** value from [sqlite3_value_subtype()] might sometimes be zero even though +** a non-zero subtype was specified by the function argument expression. +** +** [[SQLITE_RESULT_SUBTYPE]]
SQLITE_RESULT_SUBTYPE
+** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call +** [sqlite3_result_subtype()] to cause a sub-type to be associated with its +** result. +** Every function that invokes [sqlite3_result_subtype()] should have this +** property. If it does not, then the call to [sqlite3_result_subtype()] +** might become a no-op if the function is used as term in an +** [expression index]. On the other hand, SQL functions that never invoke +** [sqlite3_result_subtype()] should avoid setting this property, as the +** purpose of this property is to disable certain optimizations that are +** incompatible with subtypes. +**
+**
+*/ +#define SQLITE_DETERMINISTIC 0x000000800 +#define SQLITE_DIRECTONLY 0x000080000 +#define SQLITE_SUBTYPE 0x000100000 +#define SQLITE_INNOCUOUS 0x000200000 +#define SQLITE_RESULT_SUBTYPE 0x001000000 + +/* +** CAPI3REF: Deprecated Functions +** DEPRECATED +** +** These functions are [deprecated]. In order to maintain +** backwards compatibility with older code, these functions continue +** to be supported. However, new applications should avoid +** the use of these functions. To encourage programmers to avoid +** these functions, we will not explain what they do. +*/ +#ifndef SQLITE_OMIT_DEPRECATED +SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); +SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); +SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); +SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); +SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); +SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), + void*,sqlite3_int64); +#endif + +/* +** CAPI3REF: Obtaining SQL Values +** METHOD: sqlite3_value +** +** Summary: +**
+**
sqlite3_value_blob→BLOB value +**
sqlite3_value_double→REAL value +**
sqlite3_value_int→32-bit INTEGER value +**
sqlite3_value_int64→64-bit INTEGER value +**
sqlite3_value_pointer→Pointer value +**
sqlite3_value_text→UTF-8 TEXT value +**
sqlite3_value_text16→UTF-16 TEXT value in +** the native byteorder +**
sqlite3_value_text16be→UTF-16be TEXT value +**
sqlite3_value_text16le→UTF-16le TEXT value +**
    +**
sqlite3_value_bytes→Size of a BLOB +** or a UTF-8 TEXT in bytes +**
sqlite3_value_bytes16   +** →  Size of UTF-16 +** TEXT in bytes +**
sqlite3_value_type→Default +** datatype of the value +**
sqlite3_value_numeric_type   +** →  Best numeric datatype of the value +**
sqlite3_value_nochange   +** →  True if the column is unchanged in an UPDATE +** against a virtual table. +**
sqlite3_value_frombind   +** →  True if value originated from a [bound parameter] +**
+** +** Details: +** +** These routines extract type, size, and content information from +** [protected sqlite3_value] objects. Protected sqlite3_value objects +** are used to pass parameter information into the functions that +** implement [application-defined SQL functions] and [virtual tables]. +** +** These routines work only with [protected sqlite3_value] objects. +** Any attempt to use these routines on an [unprotected sqlite3_value] +** is not threadsafe. +** +** ^These routines work just like the corresponding [column access functions] +** except that these routines take a single [protected sqlite3_value] object +** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. +** +** ^The sqlite3_value_text16() interface extracts a UTF-16 string +** in the native byte-order of the host machine. ^The +** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces +** extract UTF-16 strings as big-endian and little-endian respectively. +** +** ^If [sqlite3_value] object V was initialized +** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] +** and if X and Y are strings that compare equal according to strcmp(X,Y), +** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, +** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() +** routine is part of the [pointer passing interface] added for SQLite 3.20.0. +** +** ^(The sqlite3_value_type(V) interface returns the +** [SQLITE_INTEGER | datatype code] for the initial datatype of the +** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], +** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ +** Other interfaces might change the datatype for an sqlite3_value object. +** For example, if the datatype is initially SQLITE_INTEGER and +** sqlite3_value_text(V) is called to extract a text value for that +** integer, then subsequent calls to sqlite3_value_type(V) might return +** SQLITE_TEXT. Whether or not a persistent internal datatype conversion +** occurs is undefined and may change from one release of SQLite to the next. +** +** ^(The sqlite3_value_numeric_type() interface attempts to apply +** numeric affinity to the value. This means that an attempt is +** made to convert the value to an integer or floating point. If +** such a conversion is possible without loss of information (in other +** words, if the value is a string that looks like a number) +** then the conversion is performed. Otherwise no conversion occurs. +** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ +** +** ^Within the [xUpdate] method of a [virtual table], the +** sqlite3_value_nochange(X) interface returns true if and only if +** the column corresponding to X is unchanged by the UPDATE operation +** that the xUpdate method call was invoked to implement and if +** and the prior [xColumn] method call that was invoked to extracted +** the value for that column returned without setting a result (probably +** because it queried [sqlite3_vtab_nochange()] and found that the column +** was unchanging). ^Within an [xUpdate] method, any value for which +** sqlite3_value_nochange(X) is true will in all other respects appear +** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other +** than within an [xUpdate] method call for an UPDATE statement, then +** the return value is arbitrary and meaningless. +** +** ^The sqlite3_value_frombind(X) interface returns non-zero if the +** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] +** interfaces. ^If X comes from an SQL literal value, or a table column, +** or an expression, then sqlite3_value_frombind(X) returns zero. +** +** Please pay particular attention to the fact that the pointer returned +** from [sqlite3_value_blob()], [sqlite3_value_text()], or +** [sqlite3_value_text16()] can be invalidated by a subsequent call to +** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], +** or [sqlite3_value_text16()]. +** +** These routines must be called from the same thread as +** the SQL function that supplied the [sqlite3_value*] parameters. +** +** As long as the input parameter is correct, these routines can only +** fail if an out-of-memory error occurs during a format conversion. +** Only the following subset of interfaces are subject to out-of-memory +** errors: +** +**
    +**
  • sqlite3_value_blob() +**
  • sqlite3_value_text() +**
  • sqlite3_value_text16() +**
  • sqlite3_value_text16le() +**
  • sqlite3_value_text16be() +**
  • sqlite3_value_bytes() +**
  • sqlite3_value_bytes16() +**
+** +** If an out-of-memory error occurs, then the return value from these +** routines is the same as if the column had contained an SQL NULL value. +** Valid SQL NULL returns can be distinguished from out-of-memory errors +** by invoking the [sqlite3_errcode()] immediately after the suspect +** return value is obtained and before any +** other SQLite interface is called on the same [database connection]. +*/ +SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); +SQLITE_API double sqlite3_value_double(sqlite3_value*); +SQLITE_API int sqlite3_value_int(sqlite3_value*); +SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); +SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); +SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); +SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); +SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); +SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); +SQLITE_API int sqlite3_value_bytes(sqlite3_value*); +SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); +SQLITE_API int sqlite3_value_type(sqlite3_value*); +SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); +SQLITE_API int sqlite3_value_nochange(sqlite3_value*); +SQLITE_API int sqlite3_value_frombind(sqlite3_value*); + +/* +** CAPI3REF: Report the internal text encoding state of an sqlite3_value object +** METHOD: sqlite3_value +** +** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8], +** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding +** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X) +** returns something other than SQLITE_TEXT, then the return value from +** sqlite3_value_encoding(X) is meaningless. ^Calls to +** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)], +** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or +** [sqlite3_value_bytes16(X)] might change the encoding of the value X and +** thus change the return from subsequent calls to sqlite3_value_encoding(X). +** +** This routine is intended for used by applications that test and validate +** the SQLite implementation. This routine is inquiring about the opaque +** internal state of an [sqlite3_value] object. Ordinary applications should +** not need to know what the internal state of an sqlite3_value object is and +** hence should not need to use this interface. +*/ +SQLITE_API int sqlite3_value_encoding(sqlite3_value*); + +/* +** CAPI3REF: Finding The Subtype Of SQL Values +** METHOD: sqlite3_value +** +** The sqlite3_value_subtype(V) function returns the subtype for +** an [application-defined SQL function] argument V. The subtype +** information can be used to pass a limited amount of context from +** one SQL function to another. Use the [sqlite3_result_subtype()] +** routine to set the subtype for the return value of an SQL function. +** +** Every [application-defined SQL function] that invoke this interface +** should include the [SQLITE_SUBTYPE] property in the text +** encoding argument when the function is [sqlite3_create_function|registered]. +** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype() +** might return zero instead of the upstream subtype in some corner cases. +*/ +SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); + +/* +** CAPI3REF: Copy And Free SQL Values +** METHOD: sqlite3_value +** +** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] +** object D and returns a pointer to that copy. ^The [sqlite3_value] returned +** is a [protected sqlite3_value] object even if the input is not. +** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a +** memory allocation fails. ^If V is a [pointer value], then the result +** of sqlite3_value_dup(V) is a NULL value. +** +** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object +** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer +** then sqlite3_value_free(V) is a harmless no-op. +*/ +SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); +SQLITE_API void sqlite3_value_free(sqlite3_value*); + +/* +** CAPI3REF: Obtain Aggregate Function Context +** METHOD: sqlite3_context +** +** Implementations of aggregate SQL functions use this +** routine to allocate memory for storing their state. +** +** ^The first time the sqlite3_aggregate_context(C,N) routine is called +** for a particular aggregate function, SQLite allocates +** N bytes of memory, zeroes out that memory, and returns a pointer +** to the new memory. ^On second and subsequent calls to +** sqlite3_aggregate_context() for the same aggregate function instance, +** the same buffer is returned. Sqlite3_aggregate_context() is normally +** called once for each invocation of the xStep callback and then one +** last time when the xFinal callback is invoked. ^(When no rows match +** an aggregate query, the xStep() callback of the aggregate function +** implementation is never called and xFinal() is called exactly once. +** In those cases, sqlite3_aggregate_context() might be called for the +** first time from within xFinal().)^ +** +** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer +** when first called if N is less than or equal to zero or if a memory +** allocation error occurs. +** +** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is +** determined by the N parameter on first successful call. Changing the +** value of N in any subsequent call to sqlite3_aggregate_context() within +** the same aggregate function instance will not resize the memory +** allocation.)^ Within the xFinal callback, it is customary to set +** N=0 in calls to sqlite3_aggregate_context(C,N) so that no +** pointless memory allocations occur. +** +** ^SQLite automatically frees the memory allocated by +** sqlite3_aggregate_context() when the aggregate query concludes. +** +** The first parameter must be a copy of the +** [sqlite3_context | SQL function context] that is the first parameter +** to the xStep or xFinal callback routine that implements the aggregate +** function. +** +** This routine must be called from the same thread in which +** the aggregate SQL function is running. +*/ +SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); + +/* +** CAPI3REF: User Data For Functions +** METHOD: sqlite3_context +** +** ^The sqlite3_user_data() interface returns a copy of +** the pointer that was the pUserData parameter (the 5th parameter) +** of the [sqlite3_create_function()] +** and [sqlite3_create_function16()] routines that originally +** registered the application defined function. +** +** This routine must be called from the same thread in which +** the application-defined function is running. +*/ +SQLITE_API void *sqlite3_user_data(sqlite3_context*); + +/* +** CAPI3REF: Database Connection For Functions +** METHOD: sqlite3_context +** +** ^The sqlite3_context_db_handle() interface returns a copy of +** the pointer to the [database connection] (the 1st parameter) +** of the [sqlite3_create_function()] +** and [sqlite3_create_function16()] routines that originally +** registered the application defined function. +*/ +SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); + +/* +** CAPI3REF: Function Auxiliary Data +** METHOD: sqlite3_context +** +** These functions may be used by (non-aggregate) SQL functions to +** associate auxiliary data with argument values. If the same argument +** value is passed to multiple invocations of the same SQL function during +** query execution, under some circumstances the associated auxiliary data +** might be preserved. An example of where this might be useful is in a +** regular-expression matching function. The compiled version of the regular +** expression can be stored as auxiliary data associated with the pattern string. +** Then as long as the pattern string remains the same, +** the compiled regular expression can be reused on multiple +** invocations of the same function. +** +** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary data +** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument +** value to the application-defined function. ^N is zero for the left-most +** function argument. ^If there is no auxiliary data +** associated with the function argument, the sqlite3_get_auxdata(C,N) interface +** returns a NULL pointer. +** +** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the +** N-th argument of the application-defined function. ^Subsequent +** calls to sqlite3_get_auxdata(C,N) return P from the most recent +** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or +** NULL if the auxiliary data has been discarded. +** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, +** SQLite will invoke the destructor function X with parameter P exactly +** once, when the auxiliary data is discarded. +** SQLite is free to discard the auxiliary data at any time, including:
    +**
  • ^(when the corresponding function parameter changes)^, or +**
  • ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the +** SQL statement)^, or +**
  • ^(when sqlite3_set_auxdata() is invoked again on the same +** parameter)^, or +**
  • ^(during the original sqlite3_set_auxdata() call when a memory +** allocation error occurs.)^ +**
  • ^(during the original sqlite3_set_auxdata() call if the function +** is evaluated during query planning instead of during query execution, +** as sometimes happens with [SQLITE_ENABLE_STAT4].)^
+** +** Note the last two bullets in particular. The destructor X in +** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the +** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() +** should be called near the end of the function implementation and the +** function implementation should not make any use of P after +** sqlite3_set_auxdata() has been called. Furthermore, a call to +** sqlite3_get_auxdata() that occurs immediately after a corresponding call +** to sqlite3_set_auxdata() might still return NULL if an out-of-memory +** condition occurred during the sqlite3_set_auxdata() call or if the +** function is being evaluated during query planning rather than during +** query execution. +** +** ^(In practice, auxiliary data is preserved between function calls for +** function parameters that are compile-time constants, including literal +** values and [parameters] and expressions composed from the same.)^ +** +** The value of the N parameter to these interfaces should be non-negative. +** Future enhancements may make use of negative N values to define new +** kinds of function caching behavior. +** +** These routines must be called from the same thread in which +** the SQL function is running. +** +** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()]. +*/ +SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); +SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); + +/* +** CAPI3REF: Database Connection Client Data +** METHOD: sqlite3 +** +** These functions are used to associate one or more named pointers +** with a [database connection]. +** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P +** to be attached to [database connection] D using name N. Subsequent +** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P +** or a NULL pointer if there were no prior calls to +** sqlite3_set_clientdata() with the same values of D and N. +** Names are compared using strcmp() and are thus case sensitive. +** +** If P and X are both non-NULL, then the destructor X is invoked with +** argument P on the first of the following occurrences: +**
    +**
  • An out-of-memory error occurs during the call to +** sqlite3_set_clientdata() which attempts to register pointer P. +**
  • A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made +** with the same D and N parameters. +**
  • The database connection closes. SQLite does not make any guarantees +** about the order in which destructors are called, only that all +** destructors will be called exactly once at some point during the +** database connection closing process. +**
+** +** SQLite does not do anything with client data other than invoke +** destructors on the client data at the appropriate time. The intended +** use for client data is to provide a mechanism for wrapper libraries +** to store additional information about an SQLite database connection. +** +** There is no limit (other than available memory) on the number of different +** client data pointers (with different names) that can be attached to a +** single database connection. However, the implementation is optimized +** for the case of having only one or two different client data names. +** Applications and wrapper libraries are discouraged from using more than +** one client data name each. +** +** There is no way to enumerate the client data pointers +** associated with a database connection. The N parameter can be thought +** of as a secret key such that only code that knows the secret key is able +** to access the associated data. +** +** Security Warning: These interfaces should not be exposed in scripting +** languages or in other circumstances where it might be possible for an +** an attacker to invoke them. Any agent that can invoke these interfaces +** can probably also take control of the process. +** +** Database connection client data is only available for SQLite +** version 3.44.0 ([dateof:3.44.0]) and later. +** +** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()]. +*/ +SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*); +SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*)); + +/* +** CAPI3REF: Constants Defining Special Destructor Behavior +** +** These are special values for the destructor that is passed in as the +** final argument to routines like [sqlite3_result_blob()]. ^If the destructor +** argument is SQLITE_STATIC, it means that the content pointer is constant +** and will never change. It does not need to be destroyed. ^The +** SQLITE_TRANSIENT value means that the content will likely change in +** the near future and that SQLite should make its own private copy of +** the content before returning. +** +** The typedef is necessary to work around problems in certain +** C++ compilers. +*/ +typedef void (*sqlite3_destructor_type)(void*); +#define SQLITE_STATIC ((sqlite3_destructor_type)0) +#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) + +/* +** CAPI3REF: Setting The Result Of An SQL Function +** METHOD: sqlite3_context +** +** These routines are used by the xFunc or xFinal callbacks that +** implement SQL functions and aggregates. See +** [sqlite3_create_function()] and [sqlite3_create_function16()] +** for additional information. +** +** These functions work very much like the [parameter binding] family of +** functions used to bind values to host parameters in prepared statements. +** Refer to the [SQL parameter] documentation for additional information. +** +** ^The sqlite3_result_blob() interface sets the result from +** an application-defined function to be the BLOB whose content is pointed +** to by the second parameter and which is N bytes long where N is the +** third parameter. +** +** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) +** interfaces set the result of the application-defined function to be +** a BLOB containing all zero bytes and N bytes in size. +** +** ^The sqlite3_result_double() interface sets the result from +** an application-defined function to be a floating point value specified +** by its 2nd argument. +** +** ^The sqlite3_result_error() and sqlite3_result_error16() functions +** cause the implemented SQL function to throw an exception. +** ^SQLite uses the string pointed to by the +** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() +** as the text of an error message. ^SQLite interprets the error +** message string from sqlite3_result_error() as UTF-8. ^SQLite +** interprets the string from sqlite3_result_error16() as UTF-16 using +** the same [byte-order determination rules] as [sqlite3_bind_text16()]. +** ^If the third parameter to sqlite3_result_error() +** or sqlite3_result_error16() is negative then SQLite takes as the error +** message all text up through the first zero character. +** ^If the third parameter to sqlite3_result_error() or +** sqlite3_result_error16() is non-negative then SQLite takes that many +** bytes (not characters) from the 2nd parameter as the error message. +** ^The sqlite3_result_error() and sqlite3_result_error16() +** routines make a private copy of the error message text before +** they return. Hence, the calling function can deallocate or +** modify the text after they return without harm. +** ^The sqlite3_result_error_code() function changes the error code +** returned by SQLite as a result of an error in a function. ^By default, +** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() +** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. +** +** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an +** error indicating that a string or BLOB is too long to represent. +** +** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an +** error indicating that a memory allocation failed. +** +** ^The sqlite3_result_int() interface sets the return value +** of the application-defined function to be the 32-bit signed integer +** value given in the 2nd argument. +** ^The sqlite3_result_int64() interface sets the return value +** of the application-defined function to be the 64-bit signed integer +** value given in the 2nd argument. +** +** ^The sqlite3_result_null() interface sets the return value +** of the application-defined function to be NULL. +** +** ^The sqlite3_result_text(), sqlite3_result_text16(), +** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces +** set the return value of the application-defined function to be +** a text string which is represented as UTF-8, UTF-16 native byte order, +** UTF-16 little endian, or UTF-16 big endian, respectively. +** ^The sqlite3_result_text64() interface sets the return value of an +** application-defined function to be a text string in an encoding +** specified by the fifth (and last) parameter, which must be one +** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. +** ^SQLite takes the text result from the application from +** the 2nd parameter of the sqlite3_result_text* interfaces. +** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces +** other than sqlite3_result_text64() is negative, then SQLite computes +** the string length itself by searching the 2nd parameter for the first +** zero character. +** ^If the 3rd parameter to the sqlite3_result_text* interfaces +** is non-negative, then as many bytes (not characters) of the text +** pointed to by the 2nd parameter are taken as the application-defined +** function result. If the 3rd parameter is non-negative, then it +** must be the byte offset into the string where the NUL terminator would +** appear if the string where NUL terminated. If any NUL characters occur +** in the string at a byte offset that is less than the value of the 3rd +** parameter, then the resulting string will contain embedded NULs and the +** result of expressions operating on strings with embedded NULs is undefined. +** ^If the 4th parameter to the sqlite3_result_text* interfaces +** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that +** function as the destructor on the text or BLOB result when it has +** finished using that result. +** ^If the 4th parameter to the sqlite3_result_text* interfaces or to +** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite +** assumes that the text or BLOB result is in constant space and does not +** copy the content of the parameter nor call a destructor on the content +** when it has finished using that result. +** ^If the 4th parameter to the sqlite3_result_text* interfaces +** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT +** then SQLite makes a copy of the result into space obtained +** from [sqlite3_malloc()] before it returns. +** +** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and +** sqlite3_result_text16be() routines, and for sqlite3_result_text64() +** when the encoding is not UTF8, if the input UTF16 begins with a +** byte-order mark (BOM, U+FEFF) then the BOM is removed from the +** string and the rest of the string is interpreted according to the +** byte-order specified by the BOM. ^The byte-order specified by +** the BOM at the beginning of the text overrides the byte-order +** specified by the interface procedure. ^So, for example, if +** sqlite3_result_text16le() is invoked with text that begins +** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the +** first two bytes of input are skipped and the remaining input +** is interpreted as UTF16BE text. +** +** ^For UTF16 input text to the sqlite3_result_text16(), +** sqlite3_result_text16be(), sqlite3_result_text16le(), and +** sqlite3_result_text64() routines, if the text contains invalid +** UTF16 characters, the invalid characters might be converted +** into the unicode replacement character, U+FFFD. +** +** ^The sqlite3_result_value() interface sets the result of +** the application-defined function to be a copy of the +** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The +** sqlite3_result_value() interface makes a copy of the [sqlite3_value] +** so that the [sqlite3_value] specified in the parameter may change or +** be deallocated after sqlite3_result_value() returns without harm. +** ^A [protected sqlite3_value] object may always be used where an +** [unprotected sqlite3_value] object is required, so either +** kind of [sqlite3_value] object can be used with this interface. +** +** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an +** SQL NULL value, just like [sqlite3_result_null(C)], except that it +** also associates the host-language pointer P or type T with that +** NULL value such that the pointer can be retrieved within an +** [application-defined SQL function] using [sqlite3_value_pointer()]. +** ^If the D parameter is not NULL, then it is a pointer to a destructor +** for the P parameter. ^SQLite invokes D with P as its only argument +** when SQLite is finished with P. The T parameter should be a static +** string and preferably a string literal. The sqlite3_result_pointer() +** routine is part of the [pointer passing interface] added for SQLite 3.20.0. +** +** If these routines are called from within the different thread +** than the one containing the application-defined function that received +** the [sqlite3_context] pointer, the results are undefined. +*/ +SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); +SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, + sqlite3_uint64,void(*)(void*)); +SQLITE_API void sqlite3_result_double(sqlite3_context*, double); +SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); +SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); +SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); +SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); +SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); +SQLITE_API void sqlite3_result_int(sqlite3_context*, int); +SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); +SQLITE_API void sqlite3_result_null(sqlite3_context*); +SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); +SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, + void(*)(void*), unsigned char encoding); +SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); +SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); +SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); +SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); +SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); +SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); +SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); + + +/* +** CAPI3REF: Setting The Subtype Of An SQL Function +** METHOD: sqlite3_context +** +** The sqlite3_result_subtype(C,T) function causes the subtype of +** the result from the [application-defined SQL function] with +** [sqlite3_context] C to be the value T. Only the lower 8 bits +** of the subtype T are preserved in current versions of SQLite; +** higher order bits are discarded. +** The number of subtype bytes preserved by SQLite might increase +** in future releases of SQLite. +** +** Every [application-defined SQL function] that invokes this interface +** should include the [SQLITE_RESULT_SUBTYPE] property in its +** text encoding argument when the SQL function is +** [sqlite3_create_function|registered]. If the [SQLITE_RESULT_SUBTYPE] +** property is omitted from the function that invokes sqlite3_result_subtype(), +** then in some cases the sqlite3_result_subtype() might fail to set +** the result subtype. +** +** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any +** SQL function that invokes the sqlite3_result_subtype() interface +** and that does not have the SQLITE_RESULT_SUBTYPE property will raise +** an error. Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1 +** by default. +*/ +SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); + +/* +** CAPI3REF: Define New Collating Sequences +** METHOD: sqlite3 +** +** ^These functions add, remove, or modify a [collation] associated +** with the [database connection] specified as the first argument. +** +** ^The name of the collation is a UTF-8 string +** for sqlite3_create_collation() and sqlite3_create_collation_v2() +** and a UTF-16 string in native byte order for sqlite3_create_collation16(). +** ^Collation names that compare equal according to [sqlite3_strnicmp()] are +** considered to be the same name. +** +** ^(The third argument (eTextRep) must be one of the constants: +**
    +**
  • [SQLITE_UTF8], +**
  • [SQLITE_UTF16LE], +**
  • [SQLITE_UTF16BE], +**
  • [SQLITE_UTF16], or +**
  • [SQLITE_UTF16_ALIGNED]. +**
)^ +** ^The eTextRep argument determines the encoding of strings passed +** to the collating function callback, xCompare. +** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep +** force strings to be UTF16 with native byte order. +** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin +** on an even byte address. +** +** ^The fourth argument, pArg, is an application data pointer that is passed +** through as the first argument to the collating function callback. +** +** ^The fifth argument, xCompare, is a pointer to the collating function. +** ^Multiple collating functions can be registered using the same name but +** with different eTextRep parameters and SQLite will use whichever +** function requires the least amount of data transformation. +** ^If the xCompare argument is NULL then the collating function is +** deleted. ^When all collating functions having the same name are deleted, +** that collation is no longer usable. +** +** ^The collating function callback is invoked with a copy of the pArg +** application data pointer and with two strings in the encoding specified +** by the eTextRep argument. The two integer parameters to the collating +** function callback are the length of the two strings, in bytes. The collating +** function must return an integer that is negative, zero, or positive +** if the first string is less than, equal to, or greater than the second, +** respectively. A collating function must always return the same answer +** given the same inputs. If two or more collating functions are registered +** to the same collation name (using different eTextRep values) then all +** must give an equivalent answer when invoked with equivalent strings. +** The collating function must obey the following properties for all +** strings A, B, and C: +** +**
    +**
  1. If A==B then B==A. +**
  2. If A==B and B==C then A==C. +**
  3. If A<B THEN B>A. +**
  4. If A<B and B<C then A<C. +**
+** +** If a collating function fails any of the above constraints and that +** collating function is registered and used, then the behavior of SQLite +** is undefined. +** +** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() +** with the addition that the xDestroy callback is invoked on pArg when +** the collating function is deleted. +** ^Collating functions are deleted when they are overridden by later +** calls to the collation creation functions or when the +** [database connection] is closed using [sqlite3_close()]. +** +** ^The xDestroy callback is not called if the +** sqlite3_create_collation_v2() function fails. Applications that invoke +** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should +** check the return code and dispose of the application data pointer +** themselves rather than expecting SQLite to deal with it for them. +** This is different from every other SQLite interface. The inconsistency +** is unfortunate but cannot be changed without breaking backwards +** compatibility. +** +** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. +*/ +SQLITE_API int sqlite3_create_collation( + sqlite3*, + const char *zName, + int eTextRep, + void *pArg, + int(*xCompare)(void*,int,const void*,int,const void*) +); +SQLITE_API int sqlite3_create_collation_v2( + sqlite3*, + const char *zName, + int eTextRep, + void *pArg, + int(*xCompare)(void*,int,const void*,int,const void*), + void(*xDestroy)(void*) +); +SQLITE_API int sqlite3_create_collation16( + sqlite3*, + const void *zName, + int eTextRep, + void *pArg, + int(*xCompare)(void*,int,const void*,int,const void*) +); + +/* +** CAPI3REF: Collation Needed Callbacks +** METHOD: sqlite3 +** +** ^To avoid having to register all collation sequences before a database +** can be used, a single callback function may be registered with the +** [database connection] to be invoked whenever an undefined collation +** sequence is required. +** +** ^If the function is registered using the sqlite3_collation_needed() API, +** then it is passed the names of undefined collation sequences as strings +** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, +** the names are passed as UTF-16 in machine native byte order. +** ^A call to either function replaces the existing collation-needed callback. +** +** ^(When the callback is invoked, the first argument passed is a copy +** of the second argument to sqlite3_collation_needed() or +** sqlite3_collation_needed16(). The second argument is the database +** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], +** or [SQLITE_UTF16LE], indicating the most desirable form of the collation +** sequence function required. The fourth parameter is the name of the +** required collation sequence.)^ +** +** The callback function should register the desired collation using +** [sqlite3_create_collation()], [sqlite3_create_collation16()], or +** [sqlite3_create_collation_v2()]. +*/ +SQLITE_API int sqlite3_collation_needed( + sqlite3*, + void*, + void(*)(void*,sqlite3*,int eTextRep,const char*) +); +SQLITE_API int sqlite3_collation_needed16( + sqlite3*, + void*, + void(*)(void*,sqlite3*,int eTextRep,const void*) +); + +#ifdef SQLITE_ENABLE_CEROD +/* +** Specify the activation key for a CEROD database. Unless +** activated, none of the CEROD routines will work. +*/ +SQLITE_API void sqlite3_activate_cerod( + const char *zPassPhrase /* Activation phrase */ +); +#endif + +/* +** CAPI3REF: Suspend Execution For A Short Time +** +** The sqlite3_sleep() function causes the current thread to suspend execution +** for at least a number of milliseconds specified in its parameter. +** +** If the operating system does not support sleep requests with +** millisecond time resolution, then the time will be rounded up to +** the nearest second. The number of milliseconds of sleep actually +** requested from the operating system is returned. +** +** ^SQLite implements this interface by calling the xSleep() +** method of the default [sqlite3_vfs] object. If the xSleep() method +** of the default VFS is not implemented correctly, or not implemented at +** all, then the behavior of sqlite3_sleep() may deviate from the description +** in the previous paragraphs. +** +** If a negative argument is passed to sqlite3_sleep() the results vary by +** VFS and operating system. Some system treat a negative argument as an +** instruction to sleep forever. Others understand it to mean do not sleep +** at all. ^In SQLite version 3.42.0 and later, a negative +** argument passed into sqlite3_sleep() is changed to zero before it is relayed +** down into the xSleep method of the VFS. +*/ +SQLITE_API int sqlite3_sleep(int); + +/* +** CAPI3REF: Name Of The Folder Holding Temporary Files +** +** ^(If this global variable is made to point to a string which is +** the name of a folder (a.k.a. directory), then all temporary files +** created by SQLite when using a built-in [sqlite3_vfs | VFS] +** will be placed in that directory.)^ ^If this variable +** is a NULL pointer, then SQLite performs a search for an appropriate +** temporary file directory. +** +** Applications are strongly discouraged from using this global variable. +** It is required to set a temporary folder on Windows Runtime (WinRT). +** But for all other platforms, it is highly recommended that applications +** neither read nor write this variable. This global variable is a relic +** that exists for backwards compatibility of legacy applications and should +** be avoided in new projects. +** +** It is not safe to read or modify this variable in more than one +** thread at a time. It is not safe to read or modify this variable +** if a [database connection] is being used at the same time in a separate +** thread. +** It is intended that this variable be set once +** as part of process initialization and before any SQLite interface +** routines have been called and that this variable remain unchanged +** thereafter. +** +** ^The [temp_store_directory pragma] may modify this variable and cause +** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, +** the [temp_store_directory pragma] always assumes that any string +** that this variable points to is held in memory obtained from +** [sqlite3_malloc] and the pragma may attempt to free that memory +** using [sqlite3_free]. +** Hence, if this variable is modified directly, either it should be +** made NULL or made to point to memory obtained from [sqlite3_malloc] +** or else the use of the [temp_store_directory pragma] should be avoided. +** Except when requested by the [temp_store_directory pragma], SQLite +** does not free the memory that sqlite3_temp_directory points to. If +** the application wants that memory to be freed, it must do +** so itself, taking care to only do so after all [database connection] +** objects have been destroyed. +** +** Note to Windows Runtime users: The temporary directory must be set +** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various +** features that require the use of temporary files may fail. Here is an +** example of how to do this using C++ with the Windows Runtime: +** +** 
+** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
+**       TemporaryFolder->Path->Data();
+** char zPathBuf[MAX_PATH + 1];
+** memset(zPathBuf, 0, sizeof(zPathBuf));
+** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
+**       NULL, NULL);
+** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
+**
+*/ +SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; + +/* +** CAPI3REF: Name Of The Folder Holding Database Files +** +** ^(If this global variable is made to point to a string which is +** the name of a folder (a.k.a. directory), then all database files +** specified with a relative pathname and created or accessed by +** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed +** to be relative to that directory.)^ ^If this variable is a NULL +** pointer, then SQLite assumes that all database files specified +** with a relative pathname are relative to the current directory +** for the process. Only the windows VFS makes use of this global +** variable; it is ignored by the unix VFS. +** +** Changing the value of this variable while a database connection is +** open can result in a corrupt database. +** +** It is not safe to read or modify this variable in more than one +** thread at a time. It is not safe to read or modify this variable +** if a [database connection] is being used at the same time in a separate +** thread. +** It is intended that this variable be set once +** as part of process initialization and before any SQLite interface +** routines have been called and that this variable remain unchanged +** thereafter. +** +** ^The [data_store_directory pragma] may modify this variable and cause +** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, +** the [data_store_directory pragma] always assumes that any string +** that this variable points to is held in memory obtained from +** [sqlite3_malloc] and the pragma may attempt to free that memory +** using [sqlite3_free]. +** Hence, if this variable is modified directly, either it should be +** made NULL or made to point to memory obtained from [sqlite3_malloc] +** or else the use of the [data_store_directory pragma] should be avoided. +*/ +SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; + +/* +** CAPI3REF: Win32 Specific Interface +** +** These interfaces are available only on Windows. The +** [sqlite3_win32_set_directory] interface is used to set the value associated +** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to +** zValue, depending on the value of the type parameter. The zValue parameter +** should be NULL to cause the previous value to be freed via [sqlite3_free]; +** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] +** prior to being used. The [sqlite3_win32_set_directory] interface returns +** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, +** or [SQLITE_NOMEM] if memory could not be allocated. The value of the +** [sqlite3_data_directory] variable is intended to act as a replacement for +** the current directory on the sub-platforms of Win32 where that concept is +** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and +** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the +** sqlite3_win32_set_directory interface except the string parameter must be +** UTF-8 or UTF-16, respectively. +*/ +SQLITE_API int sqlite3_win32_set_directory( + unsigned long type, /* Identifier for directory being set or reset */ + void *zValue /* New value for directory being set or reset */ +); +SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); +SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); + +/* +** CAPI3REF: Win32 Directory Types +** +** These macros are only available on Windows. They define the allowed values +** for the type argument to the [sqlite3_win32_set_directory] interface. +*/ +#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 +#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 + +/* +** CAPI3REF: Test For Auto-Commit Mode +** KEYWORDS: {autocommit mode} +** METHOD: sqlite3 +** +** ^The sqlite3_get_autocommit() interface returns non-zero or +** zero if the given database connection is or is not in autocommit mode, +** respectively. ^Autocommit mode is on by default. +** ^Autocommit mode is disabled by a [BEGIN] statement. +** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. +** +** If certain kinds of errors occur on a statement within a multi-statement +** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], +** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the +** transaction might be rolled back automatically. The only way to +** find out whether SQLite automatically rolled back the transaction after +** an error is to use this function. +** +** If another thread changes the autocommit status of the database +** connection while this routine is running, then the return value +** is undefined. +*/ +SQLITE_API int sqlite3_get_autocommit(sqlite3*); + +/* +** CAPI3REF: Find The Database Handle Of A Prepared Statement +** METHOD: sqlite3_stmt +** +** ^The sqlite3_db_handle interface returns the [database connection] handle +** to which a [prepared statement] belongs. ^The [database connection] +** returned by sqlite3_db_handle is the same [database connection] +** that was the first argument +** to the [sqlite3_prepare_v2()] call (or its variants) that was used to +** create the statement in the first place. +*/ +SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); + +/* +** CAPI3REF: Return The Schema Name For A Database Connection +** METHOD: sqlite3 +** +** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name +** for the N-th database on database connection D, or a NULL pointer of N is +** out of range. An N value of 0 means the main database file. An N of 1 is +** the "temp" schema. Larger values of N correspond to various ATTACH-ed +** databases. +** +** Space to hold the string that is returned by sqlite3_db_name() is managed +** by SQLite itself. The string might be deallocated by any operation that +** changes the schema, including [ATTACH] or [DETACH] or calls to +** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that +** occur on a different thread. Applications that need to +** remember the string long-term should make their own copy. Applications that +** are accessing the same database connection simultaneously on multiple +** threads should mutex-protect calls to this API and should make their own +** private copy of the result prior to releasing the mutex. +*/ +SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N); + +/* +** CAPI3REF: Return The Filename For A Database Connection +** METHOD: sqlite3 +** +** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename +** associated with database N of connection D. +** ^If there is no attached database N on the database +** connection D, or if database N is a temporary or in-memory database, then +** this function will return either a NULL pointer or an empty string. +** +** ^The string value returned by this routine is owned and managed by +** the database connection. ^The value will be valid until the database N +** is [DETACH]-ed or until the database connection closes. +** +** ^The filename returned by this function is the output of the +** xFullPathname method of the [VFS]. ^In other words, the filename +** will be an absolute pathname, even if the filename used +** to open the database originally was a URI or relative pathname. +** +** If the filename pointer returned by this routine is not NULL, then it +** can be used as the filename input parameter to these routines: +**
    +**
  • [sqlite3_uri_parameter()] +**
  • [sqlite3_uri_boolean()] +**
  • [sqlite3_uri_int64()] +**
  • [sqlite3_filename_database()] +**
  • [sqlite3_filename_journal()] +**
  • [sqlite3_filename_wal()] +**
+*/ +SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName); + +/* +** CAPI3REF: Determine if a database is read-only +** METHOD: sqlite3 +** +** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N +** of connection D is read-only, 0 if it is read/write, or -1 if N is not +** the name of a database on connection D. +*/ +SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); + +/* +** CAPI3REF: Determine the transaction state of a database +** METHOD: sqlite3 +** +** ^The sqlite3_txn_state(D,S) interface returns the current +** [transaction state] of schema S in database connection D. ^If S is NULL, +** then the highest transaction state of any schema on database connection D +** is returned. Transaction states are (in order of lowest to highest): +**
    +**
  1. SQLITE_TXN_NONE +**
  2. SQLITE_TXN_READ +**
  3. SQLITE_TXN_WRITE +**
+** ^If the S argument to sqlite3_txn_state(D,S) is not the name of +** a valid schema, then -1 is returned. +*/ +SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema); + +/* +** CAPI3REF: Allowed return values from sqlite3_txn_state() +** KEYWORDS: {transaction state} +** +** These constants define the current transaction state of a database file. +** ^The [sqlite3_txn_state(D,S)] interface returns one of these +** constants in order to describe the transaction state of schema S +** in [database connection] D. +** +**
+** [[SQLITE_TXN_NONE]]
SQLITE_TXN_NONE
+**
The SQLITE_TXN_NONE state means that no transaction is currently +** pending.
+** +** [[SQLITE_TXN_READ]]
SQLITE_TXN_READ
+**
The SQLITE_TXN_READ state means that the database is currently +** in a read transaction. Content has been read from the database file +** but nothing in the database file has changed. The transaction state +** will advanced to SQLITE_TXN_WRITE if any changes occur and there are +** no other conflicting concurrent write transactions. The transaction +** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or +** [COMMIT].
+** +** [[SQLITE_TXN_WRITE]]
SQLITE_TXN_WRITE
+**
The SQLITE_TXN_WRITE state means that the database is currently +** in a write transaction. Content has been written to the database file +** but has not yet committed. The transaction state will change to +** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].
+*/ +#define SQLITE_TXN_NONE 0 +#define SQLITE_TXN_READ 1 +#define SQLITE_TXN_WRITE 2 + +/* +** CAPI3REF: Find the next prepared statement +** METHOD: sqlite3 +** +** ^This interface returns a pointer to the next [prepared statement] after +** pStmt associated with the [database connection] pDb. ^If pStmt is NULL +** then this interface returns a pointer to the first prepared statement +** associated with the database connection pDb. ^If no prepared statement +** satisfies the conditions of this routine, it returns NULL. +** +** The [database connection] pointer D in a call to +** [sqlite3_next_stmt(D,S)] must refer to an open database +** connection and in particular must not be a NULL pointer. +*/ +SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); + +/* +** CAPI3REF: Commit And Rollback Notification Callbacks +** METHOD: sqlite3 +** +** ^The sqlite3_commit_hook() interface registers a callback +** function to be invoked whenever a transaction is [COMMIT | committed]. +** ^Any callback set by a previous call to sqlite3_commit_hook() +** for the same database connection is overridden. +** ^The sqlite3_rollback_hook() interface registers a callback +** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. +** ^Any callback set by a previous call to sqlite3_rollback_hook() +** for the same database connection is overridden. +** ^The pArg argument is passed through to the callback. +** ^If the callback on a commit hook function returns non-zero, +** then the commit is converted into a rollback. +** +** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions +** return the P argument from the previous call of the same function +** on the same [database connection] D, or NULL for +** the first call for each function on D. +** +** The commit and rollback hook callbacks are not reentrant. +** The callback implementation must not do anything that will modify +** the database connection that invoked the callback. Any actions +** to modify the database connection must be deferred until after the +** completion of the [sqlite3_step()] call that triggered the commit +** or rollback hook in the first place. +** Note that running any other SQL statements, including SELECT statements, +** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify +** the database connections for the meaning of "modify" in this paragraph. +** +** ^Registering a NULL function disables the callback. +** +** ^When the commit hook callback routine returns zero, the [COMMIT] +** operation is allowed to continue normally. ^If the commit hook +** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. +** ^The rollback hook is invoked on a rollback that results from a commit +** hook returning non-zero, just as it would be with any other rollback. +** +** ^For the purposes of this API, a transaction is said to have been +** rolled back if an explicit "ROLLBACK" statement is executed, or +** an error or constraint causes an implicit rollback to occur. +** ^The rollback callback is not invoked if a transaction is +** automatically rolled back because the database connection is closed. +** +** See also the [sqlite3_update_hook()] interface. +*/ +SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); +SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); + +/* +** CAPI3REF: Autovacuum Compaction Amount Callback +** METHOD: sqlite3 +** +** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback +** function C that is invoked prior to each autovacuum of the database +** file. ^The callback is passed a copy of the generic data pointer (P), +** the schema-name of the attached database that is being autovacuumed, +** the size of the database file in pages, the number of free pages, +** and the number of bytes per page, respectively. The callback should +** return the number of free pages that should be removed by the +** autovacuum. ^If the callback returns zero, then no autovacuum happens. +** ^If the value returned is greater than or equal to the number of +** free pages, then a complete autovacuum happens. +** +**

^If there are multiple ATTACH-ed database files that are being +** modified as part of a transaction commit, then the autovacuum pages +** callback is invoked separately for each file. +** +**

The callback is not reentrant. The callback function should +** not attempt to invoke any other SQLite interface. If it does, bad +** things may happen, including segmentation faults and corrupt database +** files. The callback function should be a simple function that +** does some arithmetic on its input parameters and returns a result. +** +** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional +** destructor for the P parameter. ^If X is not NULL, then X(P) is +** invoked whenever the database connection closes or when the callback +** is overwritten by another invocation of sqlite3_autovacuum_pages(). +** +**

^There is only one autovacuum pages callback per database connection. +** ^Each call to the sqlite3_autovacuum_pages() interface overrides all +** previous invocations for that database connection. ^If the callback +** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, +** then the autovacuum steps callback is canceled. The return value +** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might +** be some other error code if something goes wrong. The current +** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other +** return codes might be added in future releases. +** +**

If no autovacuum pages callback is specified (the usual case) or +** a NULL pointer is provided for the callback, +** then the default behavior is to vacuum all free pages. So, in other +** words, the default behavior is the same as if the callback function +** were something like this: +** +** 

+**     unsigned int demonstration_autovac_pages_callback(
+**       void *pClientData,
+**       const char *zSchema,
+**       unsigned int nDbPage,
+**       unsigned int nFreePage,
+**       unsigned int nBytePerPage
+**     ){
+**       return nFreePage;
+**     }
+**
+*/ +SQLITE_API int sqlite3_autovacuum_pages( + sqlite3 *db, + unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), + void*, + void(*)(void*) +); + + +/* +** CAPI3REF: Data Change Notification Callbacks +** METHOD: sqlite3 +** +** ^The sqlite3_update_hook() interface registers a callback function +** with the [database connection] identified by the first argument +** to be invoked whenever a row is updated, inserted or deleted in +** a [rowid table]. +** ^Any callback set by a previous call to this function +** for the same database connection is overridden. +** +** ^The second argument is a pointer to the function to invoke when a +** row is updated, inserted or deleted in a rowid table. +** ^The first argument to the callback is a copy of the third argument +** to sqlite3_update_hook(). +** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], +** or [SQLITE_UPDATE], depending on the operation that caused the callback +** to be invoked. +** ^The third and fourth arguments to the callback contain pointers to the +** database and table name containing the affected row. +** ^The final callback parameter is the [rowid] of the row. +** ^In the case of an update, this is the [rowid] after the update takes place. +** +** ^(The update hook is not invoked when internal system tables are +** modified (i.e. sqlite_sequence).)^ +** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. +** +** ^In the current implementation, the update hook +** is not invoked when conflicting rows are deleted because of an +** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook +** invoked when rows are deleted using the [truncate optimization]. +** The exceptions defined in this paragraph might change in a future +** release of SQLite. +** +** Whether the update hook is invoked before or after the +** corresponding change is currently unspecified and may differ +** depending on the type of change. Do not rely on the order of the +** hook call with regards to the final result of the operation which +** triggers the hook. +** +** The update hook implementation must not do anything that will modify +** the database connection that invoked the update hook. Any actions +** to modify the database connection must be deferred until after the +** completion of the [sqlite3_step()] call that triggered the update hook. +** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their +** database connections for the meaning of "modify" in this paragraph. +** +** ^The sqlite3_update_hook(D,C,P) function +** returns the P argument from the previous call +** on the same [database connection] D, or NULL for +** the first call on D. +** +** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], +** and [sqlite3_preupdate_hook()] interfaces. +*/ +SQLITE_API void *sqlite3_update_hook( + sqlite3*, + void(*)(void *,int ,char const *,char const *,sqlite3_int64), + void* +); + +/* +** CAPI3REF: Enable Or Disable Shared Pager Cache +** +** ^(This routine enables or disables the sharing of the database cache +** and schema data structures between [database connection | connections] +** to the same database. Sharing is enabled if the argument is true +** and disabled if the argument is false.)^ +** +** This interface is omitted if SQLite is compiled with +** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE] +** compile-time option is recommended because the +** [use of shared cache mode is discouraged]. +** +** ^Cache sharing is enabled and disabled for an entire process. +** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). +** In prior versions of SQLite, +** sharing was enabled or disabled for each thread separately. +** +** ^(The cache sharing mode set by this interface effects all subsequent +** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. +** Existing database connections continue to use the sharing mode +** that was in effect at the time they were opened.)^ +** +** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled +** successfully. An [error code] is returned otherwise.)^ +** +** ^Shared cache is disabled by default. It is recommended that it stay +** that way. In other words, do not use this routine. This interface +** continues to be provided for historical compatibility, but its use is +** discouraged. Any use of shared cache is discouraged. If shared cache +** must be used, it is recommended that shared cache only be enabled for +** individual database connections using the [sqlite3_open_v2()] interface +** with the [SQLITE_OPEN_SHAREDCACHE] flag. +** +** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 +** and will always return SQLITE_MISUSE. On those systems, +** shared cache mode should be enabled per-database connection via +** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. +** +** This interface is threadsafe on processors where writing a +** 32-bit integer is atomic. +** +** See Also: [SQLite Shared-Cache Mode] +*/ +SQLITE_API int sqlite3_enable_shared_cache(int); + +/* +** CAPI3REF: Attempt To Free Heap Memory +** +** ^The sqlite3_release_memory() interface attempts to free N bytes +** of heap memory by deallocating non-essential memory allocations +** held by the database library. Memory used to cache database +** pages to improve performance is an example of non-essential memory. +** ^sqlite3_release_memory() returns the number of bytes actually freed, +** which might be more or less than the amount requested. +** ^The sqlite3_release_memory() routine is a no-op returning zero +** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. +** +** See also: [sqlite3_db_release_memory()] +*/ +SQLITE_API int sqlite3_release_memory(int); + +/* +** CAPI3REF: Free Memory Used By A Database Connection +** METHOD: sqlite3 +** +** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap +** memory as possible from database connection D. Unlike the +** [sqlite3_release_memory()] interface, this interface is in effect even +** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is +** omitted. +** +** See also: [sqlite3_release_memory()] +*/ +SQLITE_API int sqlite3_db_release_memory(sqlite3*); + +/* +** CAPI3REF: Impose A Limit On Heap Size +** +** These interfaces impose limits on the amount of heap memory that will be +** by all database connections within a single process. +** +** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the +** soft limit on the amount of heap memory that may be allocated by SQLite. +** ^SQLite strives to keep heap memory utilization below the soft heap +** limit by reducing the number of pages held in the page cache +** as heap memory usages approaches the limit. +** ^The soft heap limit is "soft" because even though SQLite strives to stay +** below the limit, it will exceed the limit rather than generate +** an [SQLITE_NOMEM] error. In other words, the soft heap limit +** is advisory only. +** +** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of +** N bytes on the amount of memory that will be allocated. ^The +** sqlite3_hard_heap_limit64(N) interface is similar to +** sqlite3_soft_heap_limit64(N) except that memory allocations will fail +** when the hard heap limit is reached. +** +** ^The return value from both sqlite3_soft_heap_limit64() and +** sqlite3_hard_heap_limit64() is the size of +** the heap limit prior to the call, or negative in the case of an +** error. ^If the argument N is negative +** then no change is made to the heap limit. Hence, the current +** size of heap limits can be determined by invoking +** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). +** +** ^Setting the heap limits to zero disables the heap limiter mechanism. +** +** ^The soft heap limit may not be greater than the hard heap limit. +** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) +** is invoked with a value of N that is greater than the hard heap limit, +** the soft heap limit is set to the value of the hard heap limit. +** ^The soft heap limit is automatically enabled whenever the hard heap +** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and +** the soft heap limit is outside the range of 1..N, then the soft heap +** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the +** hard heap limit is enabled makes the soft heap limit equal to the +** hard heap limit. +** +** The memory allocation limits can also be adjusted using +** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. +** +** ^(The heap limits are not enforced in the current implementation +** if one or more of following conditions are true: +** +**
    +**
  • The limit value is set to zero. +**
  • Memory accounting is disabled using a combination of the +** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and +** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. +**
  • An alternative page cache implementation is specified using +** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). +**
  • The page cache allocates from its own memory pool supplied +** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than +** from the heap. +**
)^ +** +** The circumstances under which SQLite will enforce the heap limits may +** changes in future releases of SQLite. +*/ +SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); +SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); + +/* +** CAPI3REF: Deprecated Soft Heap Limit Interface +** DEPRECATED +** +** This is a deprecated version of the [sqlite3_soft_heap_limit64()] +** interface. This routine is provided for historical compatibility +** only. All new applications should use the +** [sqlite3_soft_heap_limit64()] interface rather than this one. +*/ +SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); + + +/* +** CAPI3REF: Extract Metadata About A Column Of A Table +** METHOD: sqlite3 +** +** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns +** information about column C of table T in database D +** on [database connection] X.)^ ^The sqlite3_table_column_metadata() +** interface returns SQLITE_OK and fills in the non-NULL pointers in +** the final five arguments with appropriate values if the specified +** column exists. ^The sqlite3_table_column_metadata() interface returns +** SQLITE_ERROR if the specified column does not exist. +** ^If the column-name parameter to sqlite3_table_column_metadata() is a +** NULL pointer, then this routine simply checks for the existence of the +** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it +** does not. If the table name parameter T in a call to +** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is +** undefined behavior. +** +** ^The column is identified by the second, third and fourth parameters to +** this function. ^(The second parameter is either the name of the database +** (i.e. "main", "temp", or an attached database) containing the specified +** table or NULL.)^ ^If it is NULL, then all attached databases are searched +** for the table using the same algorithm used by the database engine to +** resolve unqualified table references. +** +** ^The third and fourth parameters to this function are the table and column +** name of the desired column, respectively. +** +** ^Metadata is returned by writing to the memory locations passed as the 5th +** and subsequent parameters to this function. ^Any of these arguments may be +** NULL, in which case the corresponding element of metadata is omitted. +** +** ^(
+** +**
Parameter Output
Type 		Description +** +**
5th const char* Data type +**
6th const char* Name of default collation sequence +**
7th int True if column has a NOT NULL constraint +**
8th int True if column is part of the PRIMARY KEY +**
9th int True if column is [AUTOINCREMENT] +**
+**
)^ +** +** ^The memory pointed to by the character pointers returned for the +** declaration type and collation sequence is valid until the next +** call to any SQLite API function. +** +** ^If the specified table is actually a view, an [error code] is returned. +** +** ^If the specified column is "rowid", "oid" or "_rowid_" and the table +** is not a [WITHOUT ROWID] table and an +** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output +** parameters are set for the explicitly declared column. ^(If there is no +** [INTEGER PRIMARY KEY] column, then the outputs +** for the [rowid] are set as follows: +** +** 
+**     data type: "INTEGER"
+**     collation sequence: "BINARY"
+**     not null: 0
+**     primary key: 1
+**     auto increment: 0
+**
)^ +** +** ^This function causes all database schemas to be read from disk and +** parsed, if that has not already been done, and returns an error if +** any errors are encountered while loading the schema. +*/ +SQLITE_API int sqlite3_table_column_metadata( + sqlite3 *db, /* Connection handle */ + const char *zDbName, /* Database name or NULL */ + const char *zTableName, /* Table name */ + const char *zColumnName, /* Column name */ + char const **pzDataType, /* OUTPUT: Declared data type */ + char const **pzCollSeq, /* OUTPUT: Collation sequence name */ + int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ + int *pPrimaryKey, /* OUTPUT: True if column part of PK */ + int *pAutoinc /* OUTPUT: True if column is auto-increment */ +); + +/* +** CAPI3REF: Load An Extension +** METHOD: sqlite3 +** +** ^This interface loads an SQLite extension library from the named file. +** +** ^The sqlite3_load_extension() interface attempts to load an +** [SQLite extension] library contained in the file zFile. If +** the file cannot be loaded directly, attempts are made to load +** with various operating-system specific extensions added. +** So for example, if "samplelib" cannot be loaded, then names like +** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might +** be tried also. +** +** ^The entry point is zProc. +** ^(zProc may be 0, in which case SQLite will try to come up with an +** entry point name on its own. It first tries "sqlite3_extension_init". +** If that does not work, it constructs a name "sqlite3_X_init" where the +** X is consists of the lower-case equivalent of all ASCII alphabetic +** characters in the filename from the last "/" to the first following +** "." and omitting any initial "lib".)^ +** ^The sqlite3_load_extension() interface returns +** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. +** ^If an error occurs and pzErrMsg is not 0, then the +** [sqlite3_load_extension()] interface shall attempt to +** fill *pzErrMsg with error message text stored in memory +** obtained from [sqlite3_malloc()]. The calling function +** should free this memory by calling [sqlite3_free()]. +** +** ^Extension loading must be enabled using +** [sqlite3_enable_load_extension()] or +** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) +** prior to calling this API, +** otherwise an error will be returned. +** +** Security warning: It is recommended that the +** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this +** interface. The use of the [sqlite3_enable_load_extension()] interface +** should be avoided. This will keep the SQL function [load_extension()] +** disabled and prevent SQL injections from giving attackers +** access to extension loading capabilities. +** +** See also the [load_extension() SQL function]. +*/ +SQLITE_API int sqlite3_load_extension( + sqlite3 *db, /* Load the extension into this database connection */ + const char *zFile, /* Name of the shared library containing extension */ + const char *zProc, /* Entry point. Derived from zFile if 0 */ + char **pzErrMsg /* Put error message here if not 0 */ +); + +/* +** CAPI3REF: Enable Or Disable Extension Loading +** METHOD: sqlite3 +** +** ^So as not to open security holes in older applications that are +** unprepared to deal with [extension loading], and as a means of disabling +** [extension loading] while evaluating user-entered SQL, the following API +** is provided to turn the [sqlite3_load_extension()] mechanism on and off. +** +** ^Extension loading is off by default. +** ^Call the sqlite3_enable_load_extension() routine with onoff==1 +** to turn extension loading on and call it with onoff==0 to turn +** it back off again. +** +** ^This interface enables or disables both the C-API +** [sqlite3_load_extension()] and the SQL function [load_extension()]. +** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) +** to enable or disable only the C-API.)^ +** +** Security warning: It is recommended that extension loading +** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method +** rather than this interface, so the [load_extension()] SQL function +** remains disabled. This will prevent SQL injections from giving attackers +** access to extension loading capabilities. +*/ +SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); + +/* +** CAPI3REF: Automatically Load Statically Linked Extensions +** +** ^This interface causes the xEntryPoint() function to be invoked for +** each new [database connection] that is created. The idea here is that +** xEntryPoint() is the entry point for a statically linked [SQLite extension] +** that is to be automatically loaded into all new database connections. +** +** ^(Even though the function prototype shows that xEntryPoint() takes +** no arguments and returns void, SQLite invokes xEntryPoint() with three +** arguments and expects an integer result as if the signature of the +** entry point where as follows: +** +** 
+**    int xEntryPoint(
+**      sqlite3 *db,
+**      const char **pzErrMsg,
+**      const struct sqlite3_api_routines *pThunk
+**    );
+**
)^ +** +** If the xEntryPoint routine encounters an error, it should make *pzErrMsg +** point to an appropriate error message (obtained from [sqlite3_mprintf()]) +** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg +** is NULL before calling the xEntryPoint(). ^SQLite will invoke +** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any +** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], +** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. +** +** ^Calling sqlite3_auto_extension(X) with an entry point X that is already +** on the list of automatic extensions is a harmless no-op. ^No entry point +** will be called more than once for each database connection that is opened. +** +** See also: [sqlite3_reset_auto_extension()] +** and [sqlite3_cancel_auto_extension()] +*/ +SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); + +/* +** CAPI3REF: Cancel Automatic Extension Loading +** +** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the +** initialization routine X that was registered using a prior call to +** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] +** routine returns 1 if initialization routine X was successfully +** unregistered and it returns 0 if X was not on the list of initialization +** routines. +*/ +SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); + +/* +** CAPI3REF: Reset Automatic Extension Loading +** +** ^This interface disables all automatic extensions previously +** registered using [sqlite3_auto_extension()]. +*/ +SQLITE_API void sqlite3_reset_auto_extension(void); + +/* +** Structures used by the virtual table interface +*/ +typedef struct sqlite3_vtab sqlite3_vtab; +typedef struct sqlite3_index_info sqlite3_index_info; +typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; +typedef struct sqlite3_module sqlite3_module; + +/* +** CAPI3REF: Virtual Table Object +** KEYWORDS: sqlite3_module {virtual table module} +** +** This structure, sometimes called a "virtual table module", +** defines the implementation of a [virtual table]. +** This structure consists mostly of methods for the module. +** +** ^A virtual table module is created by filling in a persistent +** instance of this structure and passing a pointer to that instance +** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. +** ^The registration remains valid until it is replaced by a different +** module or until the [database connection] closes. The content +** of this structure must not change while it is registered with +** any database connection. +*/ +struct sqlite3_module { + int iVersion; + int (*xCreate)(sqlite3*, void *pAux, + int argc, const char *const*argv, + sqlite3_vtab **ppVTab, char**); + int (*xConnect)(sqlite3*, void *pAux, + int argc, const char *const*argv, + sqlite3_vtab **ppVTab, char**); + int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); + int (*xDisconnect)(sqlite3_vtab *pVTab); + int (*xDestroy)(sqlite3_vtab *pVTab); + int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); + int (*xClose)(sqlite3_vtab_cursor*); + int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, + int argc, sqlite3_value **argv); + int (*xNext)(sqlite3_vtab_cursor*); + int (*xEof)(sqlite3_vtab_cursor*); + int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); + int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); + int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); + int (*xBegin)(sqlite3_vtab *pVTab); + int (*xSync)(sqlite3_vtab *pVTab); + int (*xCommit)(sqlite3_vtab *pVTab); + int (*xRollback)(sqlite3_vtab *pVTab); + int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, + void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), + void **ppArg); + int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); + /* The methods above are in version 1 of the sqlite_module object. Those + ** below are for version 2 and greater. */ + int (*xSavepoint)(sqlite3_vtab *pVTab, int); + int (*xRelease)(sqlite3_vtab *pVTab, int); + int (*xRollbackTo)(sqlite3_vtab *pVTab, int); + /* The methods above are in versions 1 and 2 of the sqlite_module object. + ** Those below are for version 3 and greater. */ + int (*xShadowName)(const char*); + /* The methods above are in versions 1 through 3 of the sqlite_module object. + ** Those below are for version 4 and greater. */ + int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema, + const char *zTabName, int mFlags, char **pzErr); +}; + +/* +** CAPI3REF: Virtual Table Indexing Information +** KEYWORDS: sqlite3_index_info +** +** The sqlite3_index_info structure and its substructures is used as part +** of the [virtual table] interface to +** pass information into and receive the reply from the [xBestIndex] +** method of a [virtual table module]. The fields under **Inputs** are the +** inputs to xBestIndex and are read-only. xBestIndex inserts its +** results into the **Outputs** fields. +** +** ^(The aConstraint[] array records WHERE clause constraints of the form: +** +**
column OP expr
+** +** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is +** stored in aConstraint[].op using one of the +** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ +** ^(The index of the column is stored in +** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the +** expr on the right-hand side can be evaluated (and thus the constraint +** is usable) and false if it cannot.)^ +** +** ^The optimizer automatically inverts terms of the form "expr OP column" +** and makes other simplifications to the WHERE clause in an attempt to +** get as many WHERE clause terms into the form shown above as possible. +** ^The aConstraint[] array only reports WHERE clause terms that are +** relevant to the particular virtual table being queried. +** +** ^Information about the ORDER BY clause is stored in aOrderBy[]. +** ^Each term of aOrderBy records a column of the ORDER BY clause. +** +** The colUsed field indicates which columns of the virtual table may be +** required by the current scan. Virtual table columns are numbered from +** zero in the order in which they appear within the CREATE TABLE statement +** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), +** the corresponding bit is set within the colUsed mask if the column may be +** required by SQLite. If the table has at least 64 columns and any column +** to the right of the first 63 is required, then bit 63 of colUsed is also +** set. In other words, column iCol may be required if the expression +** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to +** non-zero. +** +** The [xBestIndex] method must fill aConstraintUsage[] with information +** about what parameters to pass to xFilter. ^If argvIndex>0 then +** the right-hand side of the corresponding aConstraint[] is evaluated +** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit +** is true, then the constraint is assumed to be fully handled by the +** virtual table and might not be checked again by the byte code.)^ ^(The +** aConstraintUsage[].omit flag is an optimization hint. When the omit flag +** is left in its default setting of false, the constraint will always be +** checked separately in byte code. If the omit flag is change to true, then +** the constraint may or may not be checked in byte code. In other words, +** when the omit flag is true there is no guarantee that the constraint will +** not be checked again using byte code.)^ +** +** ^The idxNum and idxStr values are recorded and passed into the +** [xFilter] method. +** ^[sqlite3_free()] is used to free idxStr if and only if +** needToFreeIdxStr is true. +** +** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in +** the correct order to satisfy the ORDER BY clause so that no separate +** sorting step is required. +** +** ^The estimatedCost value is an estimate of the cost of a particular +** strategy. A cost of N indicates that the cost of the strategy is similar +** to a linear scan of an SQLite table with N rows. A cost of log(N) +** indicates that the expense of the operation is similar to that of a +** binary search on a unique indexed field of an SQLite table with N rows. +** +** ^The estimatedRows value is an estimate of the number of rows that +** will be returned by the strategy. +** +** The xBestIndex method may optionally populate the idxFlags field with a +** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - +** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite +** assumes that the strategy may visit at most one row. +** +** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then +** SQLite also assumes that if a call to the xUpdate() method is made as +** part of the same statement to delete or update a virtual table row and the +** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback +** any database changes. In other words, if the xUpdate() returns +** SQLITE_CONSTRAINT, the database contents must be exactly as they were +** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not +** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by +** the xUpdate method are automatically rolled back by SQLite. +** +** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info +** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). +** If a virtual table extension is +** used with an SQLite version earlier than 3.8.2, the results of attempting +** to read or write the estimatedRows field are undefined (but are likely +** to include crashing the application). The estimatedRows field should +** therefore only be used if [sqlite3_libversion_number()] returns a +** value greater than or equal to 3008002. Similarly, the idxFlags field +** was added for [version 3.9.0] ([dateof:3.9.0]). +** It may therefore only be used if +** sqlite3_libversion_number() returns a value greater than or equal to +** 3009000. +*/ +struct sqlite3_index_info { + /* Inputs */ + int nConstraint; /* Number of entries in aConstraint */ + struct sqlite3_index_constraint { + int iColumn; /* Column constrained. -1 for ROWID */ + unsigned char op; /* Constraint operator */ + unsigned char usable; /* True if this constraint is usable */ + int iTermOffset; /* Used internally - xBestIndex should ignore */ + } *aConstraint; /* Table of WHERE clause constraints */ + int nOrderBy; /* Number of terms in the ORDER BY clause */ + struct sqlite3_index_orderby { + int iColumn; /* Column number */ + unsigned char desc; /* True for DESC. False for ASC. */ + } *aOrderBy; /* The ORDER BY clause */ + /* Outputs */ + struct sqlite3_index_constraint_usage { + int argvIndex; /* if >0, constraint is part of argv to xFilter */ + unsigned char omit; /* Do not code a test for this constraint */ + } *aConstraintUsage; + int idxNum; /* Number used to identify the index */ + char *idxStr; /* String, possibly obtained from sqlite3_malloc */ + int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ + int orderByConsumed; /* True if output is already ordered */ + double estimatedCost; /* Estimated cost of using this index */ + /* Fields below are only available in SQLite 3.8.2 and later */ + sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ + /* Fields below are only available in SQLite 3.9.0 and later */ + int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ + /* Fields below are only available in SQLite 3.10.0 and later */ + sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ +}; + +/* +** CAPI3REF: Virtual Table Scan Flags +** +** Virtual table implementations are allowed to set the +** [sqlite3_index_info].idxFlags field to some combination of +** these bits. +*/ +#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ + +/* +** CAPI3REF: Virtual Table Constraint Operator Codes +** +** These macros define the allowed values for the +** [sqlite3_index_info].aConstraint[].op field. Each value represents +** an operator that is part of a constraint term in the WHERE clause of +** a query that uses a [virtual table]. +** +** ^The left-hand operand of the operator is given by the corresponding +** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand +** operand is the rowid. +** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET +** operators have no left-hand operand, and so for those operators the +** corresponding aConstraint[].iColumn is meaningless and should not be +** used. +** +** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through +** value 255 are reserved to represent functions that are overloaded +** by the [xFindFunction|xFindFunction method] of the virtual table +** implementation. +** +** The right-hand operands for each constraint might be accessible using +** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand +** operand is only available if it appears as a single constant literal +** in the input SQL. If the right-hand operand is another column or an +** expression (even a constant expression) or a parameter, then the +** sqlite3_vtab_rhs_value() probably will not be able to extract it. +** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and +** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand +** and hence calls to sqlite3_vtab_rhs_value() for those operators will +** always return SQLITE_NOTFOUND. +** +** The collating sequence to be used for comparison can be found using +** the [sqlite3_vtab_collation()] interface. For most real-world virtual +** tables, the collating sequence of constraints does not matter (for example +** because the constraints are numeric) and so the sqlite3_vtab_collation() +** interface is not commonly needed. +*/ +#define SQLITE_INDEX_CONSTRAINT_EQ 2 +#define SQLITE_INDEX_CONSTRAINT_GT 4 +#define SQLITE_INDEX_CONSTRAINT_LE 8 +#define SQLITE_INDEX_CONSTRAINT_LT 16 +#define SQLITE_INDEX_CONSTRAINT_GE 32 +#define SQLITE_INDEX_CONSTRAINT_MATCH 64 +#define SQLITE_INDEX_CONSTRAINT_LIKE 65 +#define SQLITE_INDEX_CONSTRAINT_GLOB 66 +#define SQLITE_INDEX_CONSTRAINT_REGEXP 67 +#define SQLITE_INDEX_CONSTRAINT_NE 68 +#define SQLITE_INDEX_CONSTRAINT_ISNOT 69 +#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 +#define SQLITE_INDEX_CONSTRAINT_ISNULL 71 +#define SQLITE_INDEX_CONSTRAINT_IS 72 +#define SQLITE_INDEX_CONSTRAINT_LIMIT 73 +#define SQLITE_INDEX_CONSTRAINT_OFFSET 74 +#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 + +/* +** CAPI3REF: Register A Virtual Table Implementation +** METHOD: sqlite3 +** +** ^These routines are used to register a new [virtual table module] name. +** ^Module names must be registered before +** creating a new [virtual table] using the module and before using a +** preexisting [virtual table] for the module. +** +** ^The module name is registered on the [database connection] specified +** by the first parameter. ^The name of the module is given by the +** second parameter. ^The third parameter is a pointer to +** the implementation of the [virtual table module]. ^The fourth +** parameter is an arbitrary client data pointer that is passed through +** into the [xCreate] and [xConnect] methods of the virtual table module +** when a new virtual table is be being created or reinitialized. +** +** ^The sqlite3_create_module_v2() interface has a fifth parameter which +** is a pointer to a destructor for the pClientData. ^SQLite will +** invoke the destructor function (if it is not NULL) when SQLite +** no longer needs the pClientData pointer. ^The destructor will also +** be invoked if the call to sqlite3_create_module_v2() fails. +** ^The sqlite3_create_module() +** interface is equivalent to sqlite3_create_module_v2() with a NULL +** destructor. +** +** ^If the third parameter (the pointer to the sqlite3_module object) is +** NULL then no new module is created and any existing modules with the +** same name are dropped. +** +** See also: [sqlite3_drop_modules()] +*/ +SQLITE_API int sqlite3_create_module( + sqlite3 *db, /* SQLite connection to register module with */ + const char *zName, /* Name of the module */ + const sqlite3_module *p, /* Methods for the module */ + void *pClientData /* Client data for xCreate/xConnect */ +); +SQLITE_API int sqlite3_create_module_v2( + sqlite3 *db, /* SQLite connection to register module with */ + const char *zName, /* Name of the module */ + const sqlite3_module *p, /* Methods for the module */ + void *pClientData, /* Client data for xCreate/xConnect */ + void(*xDestroy)(void*) /* Module destructor function */ +); + +/* +** CAPI3REF: Remove Unnecessary Virtual Table Implementations +** METHOD: sqlite3 +** +** ^The sqlite3_drop_modules(D,L) interface removes all virtual +** table modules from database connection D except those named on list L. +** The L parameter must be either NULL or a pointer to an array of pointers +** to strings where the array is terminated by a single NULL pointer. +** ^If the L parameter is NULL, then all virtual table modules are removed. +** +** See also: [sqlite3_create_module()] +*/ +SQLITE_API int sqlite3_drop_modules( + sqlite3 *db, /* Remove modules from this connection */ + const char **azKeep /* Except, do not remove the ones named here */ +); + +/* +** CAPI3REF: Virtual Table Instance Object +** KEYWORDS: sqlite3_vtab +** +** Every [virtual table module] implementation uses a subclass +** of this object to describe a particular instance +** of the [virtual table]. Each subclass will +** be tailored to the specific needs of the module implementation. +** The purpose of this superclass is to define certain fields that are +** common to all module implementations. +** +** ^Virtual tables methods can set an error message by assigning a +** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should +** take care that any prior string is freed by a call to [sqlite3_free()] +** prior to assigning a new string to zErrMsg. ^After the error message +** is delivered up to the client application, the string will be automatically +** freed by sqlite3_free() and the zErrMsg field will be zeroed. +*/ +struct sqlite3_vtab { + const sqlite3_module *pModule; /* The module for this virtual table */ + int nRef; /* Number of open cursors */ + char *zErrMsg; /* Error message from sqlite3_mprintf() */ + /* Virtual table implementations will typically add additional fields */ +}; + +/* +** CAPI3REF: Virtual Table Cursor Object +** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} +** +** Every [virtual table module] implementation uses a subclass of the +** following structure to describe cursors that point into the +** [virtual table] and are used +** to loop through the virtual table. Cursors are created using the +** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed +** by the [sqlite3_module.xClose | xClose] method. Cursors are used +** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods +** of the module. Each module implementation will define +** the content of a cursor structure to suit its own needs. +** +** This superclass exists in order to define fields of the cursor that +** are common to all implementations. +*/ +struct sqlite3_vtab_cursor { + sqlite3_vtab *pVtab; /* Virtual table of this cursor */ + /* Virtual table implementations will typically add additional fields */ +}; + +/* +** CAPI3REF: Declare The Schema Of A Virtual Table +** +** ^The [xCreate] and [xConnect] methods of a +** [virtual table module] call this interface +** to declare the format (the names and datatypes of the columns) of +** the virtual tables they implement. +*/ +SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); + +/* +** CAPI3REF: Overload A Function For A Virtual Table +** METHOD: sqlite3 +** +** ^(Virtual tables can provide alternative implementations of functions +** using the [xFindFunction] method of the [virtual table module]. +** But global versions of those functions +** must exist in order to be overloaded.)^ +** +** ^(This API makes sure a global version of a function with a particular +** name and number of parameters exists. If no such function exists +** before this API is called, a new function is created.)^ ^The implementation +** of the new function always causes an exception to be thrown. So +** the new function is not good for anything by itself. Its only +** purpose is to be a placeholder function that can be overloaded +** by a [virtual table]. +*/ +SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); + +/* +** CAPI3REF: A Handle To An Open BLOB +** KEYWORDS: {BLOB handle} {BLOB handles} +** +** An instance of this object represents an open BLOB on which +** [sqlite3_blob_open | incremental BLOB I/O] can be performed. +** ^Objects of this type are created by [sqlite3_blob_open()] +** and destroyed by [sqlite3_blob_close()]. +** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces +** can be used to read or write small subsections of the BLOB. +** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. +*/ +typedef struct sqlite3_blob sqlite3_blob; + +/* +** CAPI3REF: Open A BLOB For Incremental I/O +** METHOD: sqlite3 +** CONSTRUCTOR: sqlite3_blob +** +** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located +** in row iRow, column zColumn, table zTable in database zDb; +** in other words, the same BLOB that would be selected by: +** +** 
+**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
+**
)^ +** +** ^(Parameter zDb is not the filename that contains the database, but +** rather the symbolic name of the database. For attached databases, this is +** the name that appears after the AS keyword in the [ATTACH] statement. +** For the main database file, the database name is "main". For TEMP +** tables, the database name is "temp".)^ +** +** ^If the flags parameter is non-zero, then the BLOB is opened for read +** and write access. ^If the flags parameter is zero, the BLOB is opened for +** read-only access. +** +** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored +** in *ppBlob. Otherwise an [error code] is returned and, unless the error +** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided +** the API is not misused, it is always safe to call [sqlite3_blob_close()] +** on *ppBlob after this function it returns. +** +** This function fails with SQLITE_ERROR if any of the following are true: +**
    +**
  • ^(Database zDb does not exist)^, +**
  • ^(Table zTable does not exist within database zDb)^, +**
  • ^(Table zTable is a WITHOUT ROWID table)^, +**
  • ^(Column zColumn does not exist)^, +**
  • ^(Row iRow is not present in the table)^, +**
  • ^(The specified column of row iRow contains a value that is not +** a TEXT or BLOB value)^, +**
  • ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE +** constraint and the blob is being opened for read/write access)^, +**
  • ^([foreign key constraints | Foreign key constraints] are enabled, +** column zColumn is part of a [child key] definition and the blob is +** being opened for read/write access)^. +**
+** +** ^Unless it returns SQLITE_MISUSE, this function sets the +** [database connection] error code and message accessible via +** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. +** +** A BLOB referenced by sqlite3_blob_open() may be read using the +** [sqlite3_blob_read()] interface and modified by using +** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a +** different row of the same table using the [sqlite3_blob_reopen()] +** interface. However, the column, table, or database of a [BLOB handle] +** cannot be changed after the [BLOB handle] is opened. +** +** ^(If the row that a BLOB handle points to is modified by an +** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects +** then the BLOB handle is marked as "expired". +** This is true if any column of the row is changed, even a column +** other than the one the BLOB handle is open on.)^ +** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for +** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. +** ^(Changes written into a BLOB prior to the BLOB expiring are not +** rolled back by the expiration of the BLOB. Such changes will eventually +** commit if the transaction continues to completion.)^ +** +** ^Use the [sqlite3_blob_bytes()] interface to determine the size of +** the opened blob. ^The size of a blob may not be changed by this +** interface. Use the [UPDATE] SQL command to change the size of a +** blob. +** +** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces +** and the built-in [zeroblob] SQL function may be used to create a +** zero-filled blob to read or write using the incremental-blob interface. +** +** To avoid a resource leak, every open [BLOB handle] should eventually +** be released by a call to [sqlite3_blob_close()]. +** +** See also: [sqlite3_blob_close()], +** [sqlite3_blob_reopen()], [sqlite3_blob_read()], +** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. +*/ +SQLITE_API int sqlite3_blob_open( + sqlite3*, + const char *zDb, + const char *zTable, + const char *zColumn, + sqlite3_int64 iRow, + int flags, + sqlite3_blob **ppBlob +); + +/* +** CAPI3REF: Move a BLOB Handle to a New Row +** METHOD: sqlite3_blob +** +** ^This function is used to move an existing [BLOB handle] so that it points +** to a different row of the same database table. ^The new row is identified +** by the rowid value passed as the second argument. Only the row can be +** changed. ^The database, table and column on which the blob handle is open +** remain the same. Moving an existing [BLOB handle] to a new row is +** faster than closing the existing handle and opening a new one. +** +** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - +** it must exist and there must be either a blob or text value stored in +** the nominated column.)^ ^If the new row is not present in the table, or if +** it does not contain a blob or text value, or if another error occurs, an +** SQLite error code is returned and the blob handle is considered aborted. +** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or +** [sqlite3_blob_reopen()] on an aborted blob handle immediately return +** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle +** always returns zero. +** +** ^This function sets the database handle error code and message. +*/ +SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); + +/* +** CAPI3REF: Close A BLOB Handle +** DESTRUCTOR: sqlite3_blob +** +** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed +** unconditionally. Even if this routine returns an error code, the +** handle is still closed.)^ +** +** ^If the blob handle being closed was opened for read-write access, and if +** the database is in auto-commit mode and there are no other open read-write +** blob handles or active write statements, the current transaction is +** committed. ^If an error occurs while committing the transaction, an error +** code is returned and the transaction rolled back. +** +** Calling this function with an argument that is not a NULL pointer or an +** open blob handle results in undefined behavior. ^Calling this routine +** with a null pointer (such as would be returned by a failed call to +** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function +** is passed a valid open blob handle, the values returned by the +** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. +*/ +SQLITE_API int sqlite3_blob_close(sqlite3_blob *); + +/* +** CAPI3REF: Return The Size Of An Open BLOB +** METHOD: sqlite3_blob +** +** ^Returns the size in bytes of the BLOB accessible via the +** successfully opened [BLOB handle] in its only argument. ^The +** incremental blob I/O routines can only read or overwriting existing +** blob content; they cannot change the size of a blob. +** +** This routine only works on a [BLOB handle] which has been created +** by a prior successful call to [sqlite3_blob_open()] and which has not +** been closed by [sqlite3_blob_close()]. Passing any other pointer in +** to this routine results in undefined and probably undesirable behavior. +*/ +SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); + +/* +** CAPI3REF: Read Data From A BLOB Incrementally +** METHOD: sqlite3_blob +** +** ^(This function is used to read data from an open [BLOB handle] into a +** caller-supplied buffer. N bytes of data are copied into buffer Z +** from the open BLOB, starting at offset iOffset.)^ +** +** ^If offset iOffset is less than N bytes from the end of the BLOB, +** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is +** less than zero, [SQLITE_ERROR] is returned and no data is read. +** ^The size of the blob (and hence the maximum value of N+iOffset) +** can be determined using the [sqlite3_blob_bytes()] interface. +** +** ^An attempt to read from an expired [BLOB handle] fails with an +** error code of [SQLITE_ABORT]. +** +** ^(On success, sqlite3_blob_read() returns SQLITE_OK. +** Otherwise, an [error code] or an [extended error code] is returned.)^ +** +** This routine only works on a [BLOB handle] which has been created +** by a prior successful call to [sqlite3_blob_open()] and which has not +** been closed by [sqlite3_blob_close()]. Passing any other pointer in +** to this routine results in undefined and probably undesirable behavior. +** +** See also: [sqlite3_blob_write()]. +*/ +SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); + +/* +** CAPI3REF: Write Data Into A BLOB Incrementally +** METHOD: sqlite3_blob +** +** ^(This function is used to write data into an open [BLOB handle] from a +** caller-supplied buffer. N bytes of data are copied from the buffer Z +** into the open BLOB, starting at offset iOffset.)^ +** +** ^(On success, sqlite3_blob_write() returns SQLITE_OK. +** Otherwise, an [error code] or an [extended error code] is returned.)^ +** ^Unless SQLITE_MISUSE is returned, this function sets the +** [database connection] error code and message accessible via +** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. +** +** ^If the [BLOB handle] passed as the first argument was not opened for +** writing (the flags parameter to [sqlite3_blob_open()] was zero), +** this function returns [SQLITE_READONLY]. +** +** This function may only modify the contents of the BLOB; it is +** not possible to increase the size of a BLOB using this API. +** ^If offset iOffset is less than N bytes from the end of the BLOB, +** [SQLITE_ERROR] is returned and no data is written. The size of the +** BLOB (and hence the maximum value of N+iOffset) can be determined +** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less +** than zero [SQLITE_ERROR] is returned and no data is written. +** +** ^An attempt to write to an expired [BLOB handle] fails with an +** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred +** before the [BLOB handle] expired are not rolled back by the +** expiration of the handle, though of course those changes might +** have been overwritten by the statement that expired the BLOB handle +** or by other independent statements. +** +** This routine only works on a [BLOB handle] which has been created +** by a prior successful call to [sqlite3_blob_open()] and which has not +** been closed by [sqlite3_blob_close()]. Passing any other pointer in +** to this routine results in undefined and probably undesirable behavior. +** +** See also: [sqlite3_blob_read()]. +*/ +SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); + +/* +** CAPI3REF: Virtual File System Objects +** +** A virtual filesystem (VFS) is an [sqlite3_vfs] object +** that SQLite uses to interact +** with the underlying operating system. Most SQLite builds come with a +** single default VFS that is appropriate for the host computer. +** New VFSes can be registered and existing VFSes can be unregistered. +** The following interfaces are provided. +** +** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. +** ^Names are case sensitive. +** ^Names are zero-terminated UTF-8 strings. +** ^If there is no match, a NULL pointer is returned. +** ^If zVfsName is NULL then the default VFS is returned. +** +** ^New VFSes are registered with sqlite3_vfs_register(). +** ^Each new VFS becomes the default VFS if the makeDflt flag is set. +** ^The same VFS can be registered multiple times without injury. +** ^To make an existing VFS into the default VFS, register it again +** with the makeDflt flag set. If two different VFSes with the +** same name are registered, the behavior is undefined. If a +** VFS is registered with a name that is NULL or an empty string, +** then the behavior is undefined. +** +** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. +** ^(If the default VFS is unregistered, another VFS is chosen as +** the default. The choice for the new VFS is arbitrary.)^ +*/ +SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); +SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); +SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); + +/* +** CAPI3REF: Mutexes +** +** The SQLite core uses these routines for thread +** synchronization. Though they are intended for internal +** use by SQLite, code that links against SQLite is +** permitted to use any of these routines. +** +** The SQLite source code contains multiple implementations +** of these mutex routines. An appropriate implementation +** is selected automatically at compile-time. The following +** implementations are available in the SQLite core: +** +**
    +**
  • SQLITE_MUTEX_PTHREADS +**
  • SQLITE_MUTEX_W32 +**
  • SQLITE_MUTEX_NOOP +**
+** +** The SQLITE_MUTEX_NOOP implementation is a set of routines +** that does no real locking and is appropriate for use in +** a single-threaded application. The SQLITE_MUTEX_PTHREADS and +** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix +** and Windows. +** +** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor +** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex +** implementation is included with the library. In this case the +** application must supply a custom mutex implementation using the +** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function +** before calling sqlite3_initialize() or any other public sqlite3_ +** function that calls sqlite3_initialize(). +** +** ^The sqlite3_mutex_alloc() routine allocates a new +** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() +** routine returns NULL if it is unable to allocate the requested +** mutex. The argument to sqlite3_mutex_alloc() must one of these +** integer constants: +** +**
    +**
  • SQLITE_MUTEX_FAST +**
  • SQLITE_MUTEX_RECURSIVE +**
  • SQLITE_MUTEX_STATIC_MAIN +**
  • SQLITE_MUTEX_STATIC_MEM +**
  • SQLITE_MUTEX_STATIC_OPEN +**
  • SQLITE_MUTEX_STATIC_PRNG +**
  • SQLITE_MUTEX_STATIC_LRU +**
  • SQLITE_MUTEX_STATIC_PMEM +**
  • SQLITE_MUTEX_STATIC_APP1 +**
  • SQLITE_MUTEX_STATIC_APP2 +**
  • SQLITE_MUTEX_STATIC_APP3 +**
  • SQLITE_MUTEX_STATIC_VFS1 +**
  • SQLITE_MUTEX_STATIC_VFS2 +**
  • SQLITE_MUTEX_STATIC_VFS3 +**
+** +** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) +** cause sqlite3_mutex_alloc() to create +** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE +** is used but not necessarily so when SQLITE_MUTEX_FAST is used. +** The mutex implementation does not need to make a distinction +** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does +** not want to. SQLite will only request a recursive mutex in +** cases where it really needs one. If a faster non-recursive mutex +** implementation is available on the host platform, the mutex subsystem +** might return such a mutex in response to SQLITE_MUTEX_FAST. +** +** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other +** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return +** a pointer to a static preexisting mutex. ^Nine static mutexes are +** used by the current version of SQLite. Future versions of SQLite +** may add additional static mutexes. Static mutexes are for internal +** use by SQLite only. Applications that use SQLite mutexes should +** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or +** SQLITE_MUTEX_RECURSIVE. +** +** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST +** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() +** returns a different mutex on every call. ^For the static +** mutex types, the same mutex is returned on every call that has +** the same type number. +** +** ^The sqlite3_mutex_free() routine deallocates a previously +** allocated dynamic mutex. Attempting to deallocate a static +** mutex results in undefined behavior. +** +** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt +** to enter a mutex. ^If another thread is already within the mutex, +** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return +** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] +** upon successful entry. ^(Mutexes created using +** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. +** In such cases, the +** mutex must be exited an equal number of times before another thread +** can enter.)^ If the same thread tries to enter any mutex other +** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. +** +** ^(Some systems (for example, Windows 95) do not support the operation +** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() +** will always return SQLITE_BUSY. In most cases the SQLite core only uses +** sqlite3_mutex_try() as an optimization, so this is acceptable +** behavior. The exceptions are unix builds that set the +** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working +** sqlite3_mutex_try() is required.)^ +** +** ^The sqlite3_mutex_leave() routine exits a mutex that was +** previously entered by the same thread. The behavior +** is undefined if the mutex is not currently entered by the +** calling thread or is not currently allocated. +** +** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), +** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer, +** then any of the four routines behaves as a no-op. +** +** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. +*/ +SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); +SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); +SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); +SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); +SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); + +/* +** CAPI3REF: Mutex Methods Object +** +** An instance of this structure defines the low-level routines +** used to allocate and use mutexes. +** +** Usually, the default mutex implementations provided by SQLite are +** sufficient, however the application has the option of substituting a custom +** implementation for specialized deployments or systems for which SQLite +** does not provide a suitable implementation. In this case, the application +** creates and populates an instance of this structure to pass +** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. +** Additionally, an instance of this structure can be used as an +** output variable when querying the system for the current mutex +** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. +** +** ^The xMutexInit method defined by this structure is invoked as +** part of system initialization by the sqlite3_initialize() function. +** ^The xMutexInit routine is called by SQLite exactly once for each +** effective call to [sqlite3_initialize()]. +** +** ^The xMutexEnd method defined by this structure is invoked as +** part of system shutdown by the sqlite3_shutdown() function. The +** implementation of this method is expected to release all outstanding +** resources obtained by the mutex methods implementation, especially +** those obtained by the xMutexInit method. ^The xMutexEnd() +** interface is invoked exactly once for each call to [sqlite3_shutdown()]. +** +** ^(The remaining seven methods defined by this structure (xMutexAlloc, +** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and +** xMutexNotheld) implement the following interfaces (respectively): +** +**
    +**
  • [sqlite3_mutex_alloc()]
    • +**
  • [sqlite3_mutex_free()]
    • +**
  • [sqlite3_mutex_enter()]
    • +**
  • [sqlite3_mutex_try()]
    • +**
  • [sqlite3_mutex_leave()]
    • +**
  • [sqlite3_mutex_held()]
    • +**
  • [sqlite3_mutex_notheld()]
    • +**
)^ +** +** The only difference is that the public sqlite3_XXX functions enumerated +** above silently ignore any invocations that pass a NULL pointer instead +** of a valid mutex handle. The implementations of the methods defined +** by this structure are not required to handle this case. The results +** of passing a NULL pointer instead of a valid mutex handle are undefined +** (i.e. it is acceptable to provide an implementation that segfaults if +** it is passed a NULL pointer). +** +** The xMutexInit() method must be threadsafe. It must be harmless to +** invoke xMutexInit() multiple times within the same process and without +** intervening calls to xMutexEnd(). Second and subsequent calls to +** xMutexInit() must be no-ops. +** +** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] +** and its associates). Similarly, xMutexAlloc() must not use SQLite memory +** allocation for a static mutex. ^However xMutexAlloc() may use SQLite +** memory allocation for a fast or recursive mutex. +** +** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is +** called, but only if the prior call to xMutexInit returned SQLITE_OK. +** If xMutexInit fails in any way, it is expected to clean up after itself +** prior to returning. +*/ +typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; +struct sqlite3_mutex_methods { + int (*xMutexInit)(void); + int (*xMutexEnd)(void); + sqlite3_mutex *(*xMutexAlloc)(int); + void (*xMutexFree)(sqlite3_mutex *); + void (*xMutexEnter)(sqlite3_mutex *); + int (*xMutexTry)(sqlite3_mutex *); + void (*xMutexLeave)(sqlite3_mutex *); + int (*xMutexHeld)(sqlite3_mutex *); + int (*xMutexNotheld)(sqlite3_mutex *); +}; + +/* +** CAPI3REF: Mutex Verification Routines +** +** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines +** are intended for use inside assert() statements. The SQLite core +** never uses these routines except inside an assert() and applications +** are advised to follow the lead of the core. The SQLite core only +** provides implementations for these routines when it is compiled +** with the SQLITE_DEBUG flag. External mutex implementations +** are only required to provide these routines if SQLITE_DEBUG is +** defined and if NDEBUG is not defined. +** +** These routines should return true if the mutex in their argument +** is held or not held, respectively, by the calling thread. +** +** The implementation is not required to provide versions of these +** routines that actually work. If the implementation does not provide working +** versions of these routines, it should at least provide stubs that always +** return true so that one does not get spurious assertion failures. +** +** If the argument to sqlite3_mutex_held() is a NULL pointer then +** the routine should return 1. This seems counter-intuitive since +** clearly the mutex cannot be held if it does not exist. But +** the reason the mutex does not exist is because the build is not +** using mutexes. And we do not want the assert() containing the +** call to sqlite3_mutex_held() to fail, so a non-zero return is +** the appropriate thing to do. The sqlite3_mutex_notheld() +** interface should also return 1 when given a NULL pointer. +*/ +#ifndef NDEBUG +SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); +SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); +#endif + +/* +** CAPI3REF: Mutex Types +** +** The [sqlite3_mutex_alloc()] interface takes a single argument +** which is one of these integer constants. +** +** The set of static mutexes may change from one SQLite release to the +** next. Applications that override the built-in mutex logic must be +** prepared to accommodate additional static mutexes. +*/ +#define SQLITE_MUTEX_FAST 0 +#define SQLITE_MUTEX_RECURSIVE 1 +#define SQLITE_MUTEX_STATIC_MAIN 2 +#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ +#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ +#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ +#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ +#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ +#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ +#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ +#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ +#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ +#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ +#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ +#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ +#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ + +/* Legacy compatibility: */ +#define SQLITE_MUTEX_STATIC_MASTER 2 + + +/* +** CAPI3REF: Retrieve the mutex for a database connection +** METHOD: sqlite3 +** +** ^This interface returns a pointer the [sqlite3_mutex] object that +** serializes access to the [database connection] given in the argument +** when the [threading mode] is Serialized. +** ^If the [threading mode] is Single-thread or Multi-thread then this +** routine returns a NULL pointer. +*/ +SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); + +/* +** CAPI3REF: Low-Level Control Of Database Files +** METHOD: sqlite3 +** KEYWORDS: {file control} +** +** ^The [sqlite3_file_control()] interface makes a direct call to the +** xFileControl method for the [sqlite3_io_methods] object associated +** with a particular database identified by the second argument. ^The +** name of the database is "main" for the main database or "temp" for the +** TEMP database, or the name that appears after the AS keyword for +** databases that are added using the [ATTACH] SQL command. +** ^A NULL pointer can be used in place of "main" to refer to the +** main database file. +** ^The third and fourth parameters to this routine +** are passed directly through to the second and third parameters of +** the xFileControl method. ^The return value of the xFileControl +** method becomes the return value of this routine. +** +** A few opcodes for [sqlite3_file_control()] are handled directly +** by the SQLite core and never invoke the +** sqlite3_io_methods.xFileControl method. +** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes +** a pointer to the underlying [sqlite3_file] object to be written into +** the space pointed to by the 4th parameter. The +** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns +** the [sqlite3_file] object associated with the journal file instead of +** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns +** a pointer to the underlying [sqlite3_vfs] object for the file. +** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter +** from the pager. +** +** ^If the second parameter (zDbName) does not match the name of any +** open database file, then SQLITE_ERROR is returned. ^This error +** code is not remembered and will not be recalled by [sqlite3_errcode()] +** or [sqlite3_errmsg()]. The underlying xFileControl method might +** also return SQLITE_ERROR. There is no way to distinguish between +** an incorrect zDbName and an SQLITE_ERROR return from the underlying +** xFileControl method. +** +** See also: [file control opcodes] +*/ +SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); + +/* +** CAPI3REF: Testing Interface +** +** ^The sqlite3_test_control() interface is used to read out internal +** state of SQLite and to inject faults into SQLite for testing +** purposes. ^The first parameter is an operation code that determines +** the number, meaning, and operation of all subsequent parameters. +** +** This interface is not for use by applications. It exists solely +** for verifying the correct operation of the SQLite library. Depending +** on how the SQLite library is compiled, this interface might not exist. +** +** The details of the operation codes, their meanings, the parameters +** they take, and what they do are all subject to change without notice. +** Unlike most of the SQLite API, this function is not guaranteed to +** operate consistently from one release to the next. +*/ +SQLITE_API int sqlite3_test_control(int op, ...); + +/* +** CAPI3REF: Testing Interface Operation Codes +** +** These constants are the valid operation code parameters used +** as the first argument to [sqlite3_test_control()]. +** +** These parameters and their meanings are subject to change +** without notice. These values are for testing purposes only. +** Applications should not use any of these parameters or the +** [sqlite3_test_control()] interface. +*/ +#define SQLITE_TESTCTRL_FIRST 5 +#define SQLITE_TESTCTRL_PRNG_SAVE 5 +#define SQLITE_TESTCTRL_PRNG_RESTORE 6 +#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ +#define SQLITE_TESTCTRL_FK_NO_ACTION 7 +#define SQLITE_TESTCTRL_BITVEC_TEST 8 +#define SQLITE_TESTCTRL_FAULT_INSTALL 9 +#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 +#define SQLITE_TESTCTRL_PENDING_BYTE 11 +#define SQLITE_TESTCTRL_ASSERT 12 +#define SQLITE_TESTCTRL_ALWAYS 13 +#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ +#define SQLITE_TESTCTRL_JSON_SELFCHECK 14 +#define SQLITE_TESTCTRL_OPTIMIZATIONS 15 +#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ +#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ +#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 +#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 +#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ +#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 +#define SQLITE_TESTCTRL_NEVER_CORRUPT 20 +#define SQLITE_TESTCTRL_VDBE_COVERAGE 21 +#define SQLITE_TESTCTRL_BYTEORDER 22 +#define SQLITE_TESTCTRL_ISINIT 23 +#define SQLITE_TESTCTRL_SORTER_MMAP 24 +#define SQLITE_TESTCTRL_IMPOSTER 25 +#define SQLITE_TESTCTRL_PARSER_COVERAGE 26 +#define SQLITE_TESTCTRL_RESULT_INTREAL 27 +#define SQLITE_TESTCTRL_PRNG_SEED 28 +#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 +#define SQLITE_TESTCTRL_SEEK_COUNT 30 +#define SQLITE_TESTCTRL_TRACEFLAGS 31 +#define SQLITE_TESTCTRL_TUNE 32 +#define SQLITE_TESTCTRL_LOGEST 33 +#define SQLITE_TESTCTRL_USELONGDOUBLE 34 +#define SQLITE_TESTCTRL_LAST 34 /* Largest TESTCTRL */ + +/* +** CAPI3REF: SQL Keyword Checking +** +** These routines provide access to the set of SQL language keywords +** recognized by SQLite. Applications can uses these routines to determine +** whether or not a specific identifier needs to be escaped (for example, +** by enclosing in double-quotes) so as not to confuse the parser. +** +** The sqlite3_keyword_count() interface returns the number of distinct +** keywords understood by SQLite. +** +** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and +** makes *Z point to that keyword expressed as UTF8 and writes the number +** of bytes in the keyword into *L. The string that *Z points to is not +** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns +** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z +** or L are NULL or invalid pointers then calls to +** sqlite3_keyword_name(N,Z,L) result in undefined behavior. +** +** The sqlite3_keyword_check(Z,L) interface checks to see whether or not +** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero +** if it is and zero if not. +** +** The parser used by SQLite is forgiving. It is often possible to use +** a keyword as an identifier as long as such use does not result in a +** parsing ambiguity. For example, the statement +** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and +** creates a new table named "BEGIN" with three columns named +** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid +** using keywords as identifiers. Common techniques used to avoid keyword +** name collisions include: +**
    +**
  • Put all identifier names inside double-quotes. This is the official +** SQL way to escape identifier names. +**
  • Put identifier names inside [...]. This is not standard SQL, +** but it is what SQL Server does and so lots of programmers use this +** technique. +**
  • Begin every identifier with the letter "Z" as no SQL keywords start +** with "Z". +**
  • Include a digit somewhere in every identifier name. +**
+** +** Note that the number of keywords understood by SQLite can depend on +** compile-time options. For example, "VACUUM" is not a keyword if +** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, +** new keywords may be added to future releases of SQLite. +*/ +SQLITE_API int sqlite3_keyword_count(void); +SQLITE_API int sqlite3_keyword_name(int,const char**,int*); +SQLITE_API int sqlite3_keyword_check(const char*,int); + +/* +** CAPI3REF: Dynamic String Object +** KEYWORDS: {dynamic string} +** +** An instance of the sqlite3_str object contains a dynamically-sized +** string under construction. +** +** The lifecycle of an sqlite3_str object is as follows: +**
    +**
  1. ^The sqlite3_str object is created using [sqlite3_str_new()]. +**
  2. ^Text is appended to the sqlite3_str object using various +** methods, such as [sqlite3_str_appendf()]. +**
  3. ^The sqlite3_str object is destroyed and the string it created +** is returned using the [sqlite3_str_finish()] interface. +**
+*/ +typedef struct sqlite3_str sqlite3_str; + +/* +** CAPI3REF: Create A New Dynamic String Object +** CONSTRUCTOR: sqlite3_str +** +** ^The [sqlite3_str_new(D)] interface allocates and initializes +** a new [sqlite3_str] object. To avoid memory leaks, the object returned by +** [sqlite3_str_new()] must be freed by a subsequent call to +** [sqlite3_str_finish(X)]. +** +** ^The [sqlite3_str_new(D)] interface always returns a pointer to a +** valid [sqlite3_str] object, though in the event of an out-of-memory +** error the returned object might be a special singleton that will +** silently reject new text, always return SQLITE_NOMEM from +** [sqlite3_str_errcode()], always return 0 for +** [sqlite3_str_length()], and always return NULL from +** [sqlite3_str_finish(X)]. It is always safe to use the value +** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter +** to any of the other [sqlite3_str] methods. +** +** The D parameter to [sqlite3_str_new(D)] may be NULL. If the +** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum +** length of the string contained in the [sqlite3_str] object will be +** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead +** of [SQLITE_MAX_LENGTH]. +*/ +SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); + +/* +** CAPI3REF: Finalize A Dynamic String +** DESTRUCTOR: sqlite3_str +** +** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X +** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] +** that contains the constructed string. The calling application should +** pass the returned value to [sqlite3_free()] to avoid a memory leak. +** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any +** errors were encountered during construction of the string. ^The +** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the +** string in [sqlite3_str] object X is zero bytes long. +*/ +SQLITE_API char *sqlite3_str_finish(sqlite3_str*); + +/* +** CAPI3REF: Add Content To A Dynamic String +** METHOD: sqlite3_str +** +** These interfaces add content to an sqlite3_str object previously obtained +** from [sqlite3_str_new()]. +** +** ^The [sqlite3_str_appendf(X,F,...)] and +** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] +** functionality of SQLite to append formatted text onto the end of +** [sqlite3_str] object X. +** +** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S +** onto the end of the [sqlite3_str] object X. N must be non-negative. +** S must contain at least N non-zero bytes of content. To append a +** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] +** method instead. +** +** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of +** zero-terminated string S onto the end of [sqlite3_str] object X. +** +** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the +** single-byte character C onto the end of [sqlite3_str] object X. +** ^This method can be used, for example, to add whitespace indentation. +** +** ^The [sqlite3_str_reset(X)] method resets the string under construction +** inside [sqlite3_str] object X back to zero bytes in length. +** +** These methods do not return a result code. ^If an error occurs, that fact +** is recorded in the [sqlite3_str] object and can be recovered by a +** subsequent call to [sqlite3_str_errcode(X)]. +*/ +SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); +SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); +SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); +SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); +SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); +SQLITE_API void sqlite3_str_reset(sqlite3_str*); + +/* +** CAPI3REF: Status Of A Dynamic String +** METHOD: sqlite3_str +** +** These interfaces return the current status of an [sqlite3_str] object. +** +** ^If any prior errors have occurred while constructing the dynamic string +** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return +** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns +** [SQLITE_NOMEM] following any out-of-memory error, or +** [SQLITE_TOOBIG] if the size of the dynamic string exceeds +** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. +** +** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, +** of the dynamic string under construction in [sqlite3_str] object X. +** ^The length returned by [sqlite3_str_length(X)] does not include the +** zero-termination byte. +** +** ^The [sqlite3_str_value(X)] method returns a pointer to the current +** content of the dynamic string under construction in X. The value +** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X +** and might be freed or altered by any subsequent method on the same +** [sqlite3_str] object. Applications must not used the pointer returned +** [sqlite3_str_value(X)] after any subsequent method call on the same +** object. ^Applications may change the content of the string returned +** by [sqlite3_str_value(X)] as long as they do not write into any bytes +** outside the range of 0 to [sqlite3_str_length(X)] and do not read or +** write any byte after any subsequent sqlite3_str method call. +*/ +SQLITE_API int sqlite3_str_errcode(sqlite3_str*); +SQLITE_API int sqlite3_str_length(sqlite3_str*); +SQLITE_API char *sqlite3_str_value(sqlite3_str*); + +/* +** CAPI3REF: SQLite Runtime Status +** +** ^These interfaces are used to retrieve runtime status information +** about the performance of SQLite, and optionally to reset various +** highwater marks. ^The first argument is an integer code for +** the specific parameter to measure. ^(Recognized integer codes +** are of the form [status parameters | SQLITE_STATUS_...].)^ +** ^The current value of the parameter is returned into *pCurrent. +** ^The highest recorded value is returned in *pHighwater. ^If the +** resetFlag is true, then the highest record value is reset after +** *pHighwater is written. ^(Some parameters do not record the highest +** value. For those parameters +** nothing is written into *pHighwater and the resetFlag is ignored.)^ +** ^(Other parameters record only the highwater mark and not the current +** value. For these latter parameters nothing is written into *pCurrent.)^ +** +** ^The sqlite3_status() and sqlite3_status64() routines return +** SQLITE_OK on success and a non-zero [error code] on failure. +** +** If either the current value or the highwater mark is too large to +** be represented by a 32-bit integer, then the values returned by +** sqlite3_status() are undefined. +** +** See also: [sqlite3_db_status()] +*/ +SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); +SQLITE_API int sqlite3_status64( + int op, + sqlite3_int64 *pCurrent, + sqlite3_int64 *pHighwater, + int resetFlag +); + + +/* +** CAPI3REF: Status Parameters +** KEYWORDS: {status parameters} +** +** These integer constants designate various run-time status parameters +** that can be returned by [sqlite3_status()]. +** +**
+** [[SQLITE_STATUS_MEMORY_USED]] ^(
SQLITE_STATUS_MEMORY_USED
+**
This parameter is the current amount of memory checked out +** using [sqlite3_malloc()], either directly or indirectly. The +** figure includes calls made to [sqlite3_malloc()] by the application +** and internal memory usage by the SQLite library. Auxiliary page-cache +** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in +** this parameter. The amount returned is the sum of the allocation +** sizes as reported by the xSize method in [sqlite3_mem_methods].
)^ +** +** [[SQLITE_STATUS_MALLOC_SIZE]] ^(
SQLITE_STATUS_MALLOC_SIZE
+**
This parameter records the largest memory allocation request +** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their +** internal equivalents). Only the value returned in the +** *pHighwater parameter to [sqlite3_status()] is of interest. +** The value written into the *pCurrent parameter is undefined.
)^ +** +** [[SQLITE_STATUS_MALLOC_COUNT]] ^(
SQLITE_STATUS_MALLOC_COUNT
+**
This parameter records the number of separate memory allocations +** currently checked out.
)^ +** +** [[SQLITE_STATUS_PAGECACHE_USED]] ^(
SQLITE_STATUS_PAGECACHE_USED
+**
This parameter returns the number of pages used out of the +** [pagecache memory allocator] that was configured using +** [SQLITE_CONFIG_PAGECACHE]. The +** value returned is in pages, not in bytes.
)^ +** +** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] +** ^(
SQLITE_STATUS_PAGECACHE_OVERFLOW
+**
This parameter returns the number of bytes of page cache +** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] +** buffer and where forced to overflow to [sqlite3_malloc()]. The +** returned value includes allocations that overflowed because they +** where too large (they were larger than the "sz" parameter to +** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because +** no space was left in the page cache.
)^ +** +** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(
SQLITE_STATUS_PAGECACHE_SIZE
+**
This parameter records the largest memory allocation request +** handed to the [pagecache memory allocator]. Only the value returned in the +** *pHighwater parameter to [sqlite3_status()] is of interest. +** The value written into the *pCurrent parameter is undefined.
)^ +** +** [[SQLITE_STATUS_SCRATCH_USED]]
SQLITE_STATUS_SCRATCH_USED
+**
No longer used.
+** +** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(
SQLITE_STATUS_SCRATCH_OVERFLOW
+**
No longer used.
+** +** [[SQLITE_STATUS_SCRATCH_SIZE]]
SQLITE_STATUS_SCRATCH_SIZE
+**
No longer used.
+** +** [[SQLITE_STATUS_PARSER_STACK]] ^(
SQLITE_STATUS_PARSER_STACK
+**
The *pHighwater parameter records the deepest parser stack. +** The *pCurrent value is undefined. The *pHighwater value is only +** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].
)^ +**
+** +** New status parameters may be added from time to time. +*/ +#define SQLITE_STATUS_MEMORY_USED 0 +#define SQLITE_STATUS_PAGECACHE_USED 1 +#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 +#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ +#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ +#define SQLITE_STATUS_MALLOC_SIZE 5 +#define SQLITE_STATUS_PARSER_STACK 6 +#define SQLITE_STATUS_PAGECACHE_SIZE 7 +#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ +#define SQLITE_STATUS_MALLOC_COUNT 9 + +/* +** CAPI3REF: Database Connection Status +** METHOD: sqlite3 +** +** ^This interface is used to retrieve runtime status information +** about a single [database connection]. ^The first argument is the +** database connection object to be interrogated. ^The second argument +** is an integer constant, taken from the set of +** [SQLITE_DBSTATUS options], that +** determines the parameter to interrogate. The set of +** [SQLITE_DBSTATUS options] is likely +** to grow in future releases of SQLite. +** +** ^The current value of the requested parameter is written into *pCur +** and the highest instantaneous value is written into *pHiwtr. ^If +** the resetFlg is true, then the highest instantaneous value is +** reset back down to the current value. +** +** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a +** non-zero [error code] on failure. +** +** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. +*/ +SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); + +/* +** CAPI3REF: Status Parameters for database connections +** KEYWORDS: {SQLITE_DBSTATUS options} +** +** These constants are the available integer "verbs" that can be passed as +** the second argument to the [sqlite3_db_status()] interface. +** +** New verbs may be added in future releases of SQLite. Existing verbs +** might be discontinued. Applications should check the return code from +** [sqlite3_db_status()] to make sure that the call worked. +** The [sqlite3_db_status()] interface will return a non-zero error code +** if a discontinued or unsupported verb is invoked. +** +**
+** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(
SQLITE_DBSTATUS_LOOKASIDE_USED
+**
This parameter returns the number of lookaside memory slots currently +** checked out.
)^ +** +** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(
SQLITE_DBSTATUS_LOOKASIDE_HIT
+**
This parameter returns the number of malloc attempts that were +** satisfied using lookaside memory. Only the high-water value is meaningful; +** the current value is always zero.)^ +** +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] +** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
+**
This parameter returns the number malloc attempts that might have +** been satisfied using lookaside memory but failed due to the amount of +** memory requested being larger than the lookaside slot size. +** Only the high-water value is meaningful; +** the current value is always zero.)^ +** +** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] +** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
+**
This parameter returns the number malloc attempts that might have +** been satisfied using lookaside memory but failed due to all lookaside +** memory already being in use. +** Only the high-water value is meaningful; +** the current value is always zero.)^ +** +** [[SQLITE_DBSTATUS_CACHE_USED]] ^(
SQLITE_DBSTATUS_CACHE_USED
+**
This parameter returns the approximate number of bytes of heap +** memory used by all pager caches associated with the database connection.)^ +** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. +** +** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] +** ^(
SQLITE_DBSTATUS_CACHE_USED_SHARED
+**
This parameter is similar to DBSTATUS_CACHE_USED, except that if a +** pager cache is shared between two or more connections the bytes of heap +** memory used by that pager cache is divided evenly between the attached +** connections.)^ In other words, if none of the pager caches associated +** with the database connection are shared, this request returns the same +** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are +** shared, the value returned by this call will be smaller than that returned +** by DBSTATUS_CACHE_USED. ^The highwater mark associated with +** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. +** +** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(
SQLITE_DBSTATUS_SCHEMA_USED
+**
This parameter returns the approximate number of bytes of heap +** memory used to store the schema for all databases associated +** with the connection - main, temp, and any [ATTACH]-ed databases.)^ +** ^The full amount of memory used by the schemas is reported, even if the +** schema memory is shared with other database connections due to +** [shared cache mode] being enabled. +** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. +** +** [[SQLITE_DBSTATUS_STMT_USED]] ^(
SQLITE_DBSTATUS_STMT_USED
+**
This parameter returns the approximate number of bytes of heap +** and lookaside memory used by all prepared statements associated with +** the database connection.)^ +** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. +**
+** +** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(
SQLITE_DBSTATUS_CACHE_HIT
+**
This parameter returns the number of pager cache hits that have +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT +** is always 0. +**
+** +** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(
SQLITE_DBSTATUS_CACHE_MISS
+**
This parameter returns the number of pager cache misses that have +** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS +** is always 0. +**
+** +** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(
SQLITE_DBSTATUS_CACHE_WRITE
+**
This parameter returns the number of dirty cache entries that have +** been written to disk. Specifically, the number of pages written to the +** wal file in wal mode databases, or the number of pages written to the +** database file in rollback mode databases. Any pages written as part of +** transaction rollback or database recovery operations are not included. +** If an IO or other error occurs while writing a page to disk, the effect +** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The +** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. +**
+** +** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(
SQLITE_DBSTATUS_CACHE_SPILL
+**
This parameter returns the number of dirty cache entries that have +** been written to disk in the middle of a transaction due to the page +** cache overflowing. Transactions are more efficient if they are written +** to disk all at once. When pages spill mid-transaction, that introduces +** additional overhead. This parameter can be used help identify +** inefficiencies that can be resolved by increasing the cache size. +**
+** +** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(
SQLITE_DBSTATUS_DEFERRED_FKS
+**
This parameter returns zero for the current value if and only if +** all foreign key constraints (deferred or immediate) have been +** resolved.)^ ^The highwater mark is always 0. +**
+**
+*/ +#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 +#define SQLITE_DBSTATUS_CACHE_USED 1 +#define SQLITE_DBSTATUS_SCHEMA_USED 2 +#define SQLITE_DBSTATUS_STMT_USED 3 +#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 +#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 +#define SQLITE_DBSTATUS_CACHE_HIT 7 +#define SQLITE_DBSTATUS_CACHE_MISS 8 +#define SQLITE_DBSTATUS_CACHE_WRITE 9 +#define SQLITE_DBSTATUS_DEFERRED_FKS 10 +#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 +#define SQLITE_DBSTATUS_CACHE_SPILL 12 +#define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ + + +/* +** CAPI3REF: Prepared Statement Status +** METHOD: sqlite3_stmt +** +** ^(Each prepared statement maintains various +** [SQLITE_STMTSTATUS counters] that measure the number +** of times it has performed specific operations.)^ These counters can +** be used to monitor the performance characteristics of the prepared +** statements. For example, if the number of table steps greatly exceeds +** the number of table searches or result rows, that would tend to indicate +** that the prepared statement is using a full table scan rather than +** an index. +** +** ^(This interface is used to retrieve and reset counter values from +** a [prepared statement]. The first argument is the prepared statement +** object to be interrogated. The second argument +** is an integer code for a specific [SQLITE_STMTSTATUS counter] +** to be interrogated.)^ +** ^The current value of the requested counter is returned. +** ^If the resetFlg is true, then the counter is reset to zero after this +** interface call returns. +** +** See also: [sqlite3_status()] and [sqlite3_db_status()]. +*/ +SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); + +/* +** CAPI3REF: Status Parameters for prepared statements +** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} +** +** These preprocessor macros define integer codes that name counter +** values associated with the [sqlite3_stmt_status()] interface. +** The meanings of the various counters are as follows: +** +**
+** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]]
SQLITE_STMTSTATUS_FULLSCAN_STEP
+**
^This is the number of times that SQLite has stepped forward in +** a table as part of a full table scan. Large numbers for this counter +** may indicate opportunities for performance improvement through +** careful use of indices.
+** +** [[SQLITE_STMTSTATUS_SORT]]
SQLITE_STMTSTATUS_SORT
+**
^This is the number of sort operations that have occurred. +** A non-zero value in this counter may indicate an opportunity to +** improvement performance through careful use of indices.
+** +** [[SQLITE_STMTSTATUS_AUTOINDEX]]
SQLITE_STMTSTATUS_AUTOINDEX
+**
^This is the number of rows inserted into transient indices that +** were created automatically in order to help joins run faster. +** A non-zero value in this counter may indicate an opportunity to +** improvement performance by adding permanent indices that do not +** need to be reinitialized each time the statement is run.
+** +** [[SQLITE_STMTSTATUS_VM_STEP]]
SQLITE_STMTSTATUS_VM_STEP
+**
^This is the number of virtual machine operations executed +** by the prepared statement if that number is less than or equal +** to 2147483647. The number of virtual machine operations can be +** used as a proxy for the total work done by the prepared statement. +** If the number of virtual machine operations exceeds 2147483647 +** then the value returned by this statement status code is undefined. +** +** [[SQLITE_STMTSTATUS_REPREPARE]]
SQLITE_STMTSTATUS_REPREPARE
+**
^This is the number of times that the prepare statement has been +** automatically regenerated due to schema changes or changes to +** [bound parameters] that might affect the query plan. +** +** [[SQLITE_STMTSTATUS_RUN]]
SQLITE_STMTSTATUS_RUN
+**
^This is the number of times that the prepared statement has +** been run. A single "run" for the purposes of this counter is one +** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. +** The counter is incremented on the first [sqlite3_step()] call of each +** cycle. +** +** [[SQLITE_STMTSTATUS_FILTER_MISS]] +** [[SQLITE_STMTSTATUS_FILTER HIT]] +**
SQLITE_STMTSTATUS_FILTER_HIT
+** SQLITE_STMTSTATUS_FILTER_MISS
+**
^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join +** step was bypassed because a Bloom filter returned not-found. The +** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of +** times that the Bloom filter returned a find, and thus the join step +** had to be processed as normal. +** +** [[SQLITE_STMTSTATUS_MEMUSED]]
SQLITE_STMTSTATUS_MEMUSED
+**
^This is the approximate number of bytes of heap memory +** used to store the prepared statement. ^This value is not actually +** a counter, and so the resetFlg parameter to sqlite3_stmt_status() +** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. +**
+**
+*/ +#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 +#define SQLITE_STMTSTATUS_SORT 2 +#define SQLITE_STMTSTATUS_AUTOINDEX 3 +#define SQLITE_STMTSTATUS_VM_STEP 4 +#define SQLITE_STMTSTATUS_REPREPARE 5 +#define SQLITE_STMTSTATUS_RUN 6 +#define SQLITE_STMTSTATUS_FILTER_MISS 7 +#define SQLITE_STMTSTATUS_FILTER_HIT 8 +#define SQLITE_STMTSTATUS_MEMUSED 99 + +/* +** CAPI3REF: Custom Page Cache Object +** +** The sqlite3_pcache type is opaque. It is implemented by +** the pluggable module. The SQLite core has no knowledge of +** its size or internal structure and never deals with the +** sqlite3_pcache object except by holding and passing pointers +** to the object. +** +** See [sqlite3_pcache_methods2] for additional information. +*/ +typedef struct sqlite3_pcache sqlite3_pcache; + +/* +** CAPI3REF: Custom Page Cache Object +** +** The sqlite3_pcache_page object represents a single page in the +** page cache. The page cache will allocate instances of this +** object. Various methods of the page cache use pointers to instances +** of this object as parameters or as their return value. +** +** See [sqlite3_pcache_methods2] for additional information. +*/ +typedef struct sqlite3_pcache_page sqlite3_pcache_page; +struct sqlite3_pcache_page { + void *pBuf; /* The content of the page */ + void *pExtra; /* Extra information associated with the page */ +}; + +/* +** CAPI3REF: Application Defined Page Cache. +** KEYWORDS: {page cache} +** +** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can +** register an alternative page cache implementation by passing in an +** instance of the sqlite3_pcache_methods2 structure.)^ +** In many applications, most of the heap memory allocated by +** SQLite is used for the page cache. +** By implementing a +** custom page cache using this API, an application can better control +** the amount of memory consumed by SQLite, the way in which +** that memory is allocated and released, and the policies used to +** determine exactly which parts of a database file are cached and for +** how long. +** +** The alternative page cache mechanism is an +** extreme measure that is only needed by the most demanding applications. +** The built-in page cache is recommended for most uses. +** +** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an +** internal buffer by SQLite within the call to [sqlite3_config]. Hence +** the application may discard the parameter after the call to +** [sqlite3_config()] returns.)^ +** +** [[the xInit() page cache method]] +** ^(The xInit() method is called once for each effective +** call to [sqlite3_initialize()])^ +** (usually only once during the lifetime of the process). ^(The xInit() +** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ +** The intent of the xInit() method is to set up global data structures +** required by the custom page cache implementation. +** ^(If the xInit() method is NULL, then the +** built-in default page cache is used instead of the application defined +** page cache.)^ +** +** [[the xShutdown() page cache method]] +** ^The xShutdown() method is called by [sqlite3_shutdown()]. +** It can be used to clean up +** any outstanding resources before process shutdown, if required. +** ^The xShutdown() method may be NULL. +** +** ^SQLite automatically serializes calls to the xInit method, +** so the xInit method need not be threadsafe. ^The +** xShutdown method is only called from [sqlite3_shutdown()] so it does +** not need to be threadsafe either. All other methods must be threadsafe +** in multithreaded applications. +** +** ^SQLite will never invoke xInit() more than once without an intervening +** call to xShutdown(). +** +** [[the xCreate() page cache methods]] +** ^SQLite invokes the xCreate() method to construct a new cache instance. +** SQLite will typically create one cache instance for each open database file, +** though this is not guaranteed. ^The +** first parameter, szPage, is the size in bytes of the pages that must +** be allocated by the cache. ^szPage will always a power of two. ^The +** second parameter szExtra is a number of bytes of extra storage +** associated with each page cache entry. ^The szExtra parameter will +** a number less than 250. SQLite will use the +** extra szExtra bytes on each page to store metadata about the underlying +** database page on disk. The value passed into szExtra depends +** on the SQLite version, the target platform, and how SQLite was compiled. +** ^The third argument to xCreate(), bPurgeable, is true if the cache being +** created will be used to cache database pages of a file stored on disk, or +** false if it is used for an in-memory database. The cache implementation +** does not have to do anything special based with the value of bPurgeable; +** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will +** never invoke xUnpin() except to deliberately delete a page. +** ^In other words, calls to xUnpin() on a cache with bPurgeable set to +** false will always have the "discard" flag set to true. +** ^Hence, a cache created with bPurgeable false will +** never contain any unpinned pages. +** +** [[the xCachesize() page cache method]] +** ^(The xCachesize() method may be called at any time by SQLite to set the +** suggested maximum cache-size (number of pages stored by) the cache +** instance passed as the first argument. This is the value configured using +** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable +** parameter, the implementation is not required to do anything with this +** value; it is advisory only. +** +** [[the xPagecount() page cache methods]] +** The xPagecount() method must return the number of pages currently +** stored in the cache, both pinned and unpinned. +** +** [[the xFetch() page cache methods]] +** The xFetch() method locates a page in the cache and returns a pointer to +** an sqlite3_pcache_page object associated with that page, or a NULL pointer. +** The pBuf element of the returned sqlite3_pcache_page object will be a +** pointer to a buffer of szPage bytes used to store the content of a +** single database page. The pExtra element of sqlite3_pcache_page will be +** a pointer to the szExtra bytes of extra storage that SQLite has requested +** for each entry in the page cache. +** +** The page to be fetched is determined by the key. ^The minimum key value +** is 1. After it has been retrieved using xFetch, the page is considered +** to be "pinned". +** +** If the requested page is already in the page cache, then the page cache +** implementation must return a pointer to the page buffer with its content +** intact. If the requested page is not already in the cache, then the +** cache implementation should use the value of the createFlag +** parameter to help it determined what action to take: +** +** +**
createFlag Behavior when page is not already in cache +**
0 Do not allocate a new page. Return NULL. +**
1 Allocate a new page if it easy and convenient to do so. +** Otherwise return NULL. +**
2 Make every effort to allocate a new page. Only return +** NULL if allocating a new page is effectively impossible. +**
+** +** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite +** will only use a createFlag of 2 after a prior call with a createFlag of 1 +** failed.)^ In between the xFetch() calls, SQLite may +** attempt to unpin one or more cache pages by spilling the content of +** pinned pages to disk and synching the operating system disk cache. +** +** [[the xUnpin() page cache method]] +** ^xUnpin() is called by SQLite with a pointer to a currently pinned page +** as its second argument. If the third parameter, discard, is non-zero, +** then the page must be evicted from the cache. +** ^If the discard parameter is +** zero, then the page may be discarded or retained at the discretion of +** page cache implementation. ^The page cache implementation +** may choose to evict unpinned pages at any time. +** +** The cache must not perform any reference counting. A single +** call to xUnpin() unpins the page regardless of the number of prior calls +** to xFetch(). +** +** [[the xRekey() page cache methods]] +** The xRekey() method is used to change the key value associated with the +** page passed as the second argument. If the cache +** previously contains an entry associated with newKey, it must be +** discarded. ^Any prior cache entry associated with newKey is guaranteed not +** to be pinned. +** +** When SQLite calls the xTruncate() method, the cache must discard all +** existing cache entries with page numbers (keys) greater than or equal +** to the value of the iLimit parameter passed to xTruncate(). If any +** of these pages are pinned, they are implicitly unpinned, meaning that +** they can be safely discarded. +** +** [[the xDestroy() page cache method]] +** ^The xDestroy() method is used to delete a cache allocated by xCreate(). +** All resources associated with the specified cache should be freed. ^After +** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] +** handle invalid, and will not use it with any other sqlite3_pcache_methods2 +** functions. +** +** [[the xShrink() page cache method]] +** ^SQLite invokes the xShrink() method when it wants the page cache to +** free up as much of heap memory as possible. The page cache implementation +** is not obligated to free any memory, but well-behaved implementations should +** do their best. +*/ +typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; +struct sqlite3_pcache_methods2 { + int iVersion; + void *pArg; + int (*xInit)(void*); + void (*xShutdown)(void*); + sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); + void (*xCachesize)(sqlite3_pcache*, int nCachesize); + int (*xPagecount)(sqlite3_pcache*); + sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); + void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); + void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, + unsigned oldKey, unsigned newKey); + void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); + void (*xDestroy)(sqlite3_pcache*); + void (*xShrink)(sqlite3_pcache*); +}; + +/* +** This is the obsolete pcache_methods object that has now been replaced +** by sqlite3_pcache_methods2. This object is not used by SQLite. It is +** retained in the header file for backwards compatibility only. +*/ +typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; +struct sqlite3_pcache_methods { + void *pArg; + int (*xInit)(void*); + void (*xShutdown)(void*); + sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); + void (*xCachesize)(sqlite3_pcache*, int nCachesize); + int (*xPagecount)(sqlite3_pcache*); + void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); + void (*xUnpin)(sqlite3_pcache*, void*, int discard); + void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); + void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); + void (*xDestroy)(sqlite3_pcache*); +}; + + +/* +** CAPI3REF: Online Backup Object +** +** The sqlite3_backup object records state information about an ongoing +** online backup operation. ^The sqlite3_backup object is created by +** a call to [sqlite3_backup_init()] and is destroyed by a call to +** [sqlite3_backup_finish()]. +** +** See Also: [Using the SQLite Online Backup API] +*/ +typedef struct sqlite3_backup sqlite3_backup; + +/* +** CAPI3REF: Online Backup API. +** +** The backup API copies the content of one database into another. +** It is useful either for creating backups of databases or +** for copying in-memory databases to or from persistent files. +** +** See Also: [Using the SQLite Online Backup API] +** +** ^SQLite holds a write transaction open on the destination database file +** for the duration of the backup operation. +** ^The source database is read-locked only while it is being read; +** it is not locked continuously for the entire backup operation. +** ^Thus, the backup may be performed on a live source database without +** preventing other database connections from +** reading or writing to the source database while the backup is underway. +** +** ^(To perform a backup operation: +**
    +**
  1. sqlite3_backup_init() is called once to initialize the +** backup, +**
  2. sqlite3_backup_step() is called one or more times to transfer +** the data between the two databases, and finally +**
  3. sqlite3_backup_finish() is called to release all resources +** associated with the backup operation. +**
)^ +** There should be exactly one call to sqlite3_backup_finish() for each +** successful call to sqlite3_backup_init(). +** +** [[sqlite3_backup_init()]] sqlite3_backup_init() +** +** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the +** [database connection] associated with the destination database +** and the database name, respectively. +** ^The database name is "main" for the main database, "temp" for the +** temporary database, or the name specified after the AS keyword in +** an [ATTACH] statement for an attached database. +** ^The S and M arguments passed to +** sqlite3_backup_init(D,N,S,M) identify the [database connection] +** and database name of the source database, respectively. +** ^The source and destination [database connections] (parameters S and D) +** must be different or else sqlite3_backup_init(D,N,S,M) will fail with +** an error. +** +** ^A call to sqlite3_backup_init() will fail, returning NULL, if +** there is already a read or read-write transaction open on the +** destination database. +** +** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is +** returned and an error code and error message are stored in the +** destination [database connection] D. +** ^The error code and message for the failed call to sqlite3_backup_init() +** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or +** [sqlite3_errmsg16()] functions. +** ^A successful call to sqlite3_backup_init() returns a pointer to an +** [sqlite3_backup] object. +** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and +** sqlite3_backup_finish() functions to perform the specified backup +** operation. +** +** [[sqlite3_backup_step()]] sqlite3_backup_step() +** +** ^Function sqlite3_backup_step(B,N) will copy up to N pages between +** the source and destination databases specified by [sqlite3_backup] object B. +** ^If N is negative, all remaining source pages are copied. +** ^If sqlite3_backup_step(B,N) successfully copies N pages and there +** are still more pages to be copied, then the function returns [SQLITE_OK]. +** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages +** from source to destination, then it returns [SQLITE_DONE]. +** ^If an error occurs while running sqlite3_backup_step(B,N), +** then an [error code] is returned. ^As well as [SQLITE_OK] and +** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], +** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. +** +** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if +**
    +**
  1. the destination database was opened read-only, or +**
  2. the destination database is using write-ahead-log journaling +** and the destination and source page sizes differ, or +**
  3. the destination database is an in-memory database and the +** destination and source page sizes differ. +**
)^ +** +** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then +** the [sqlite3_busy_handler | busy-handler function] +** is invoked (if one is specified). ^If the +** busy-handler returns non-zero before the lock is available, then +** [SQLITE_BUSY] is returned to the caller. ^In this case the call to +** sqlite3_backup_step() can be retried later. ^If the source +** [database connection] +** is being used to write to the source database when sqlite3_backup_step() +** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this +** case the call to sqlite3_backup_step() can be retried later on. ^(If +** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or +** [SQLITE_READONLY] is returned, then +** there is no point in retrying the call to sqlite3_backup_step(). These +** errors are considered fatal.)^ The application must accept +** that the backup operation has failed and pass the backup operation handle +** to the sqlite3_backup_finish() to release associated resources. +** +** ^The first call to sqlite3_backup_step() obtains an exclusive lock +** on the destination file. ^The exclusive lock is not released until either +** sqlite3_backup_finish() is called or the backup operation is complete +** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to +** sqlite3_backup_step() obtains a [shared lock] on the source database that +** lasts for the duration of the sqlite3_backup_step() call. +** ^Because the source database is not locked between calls to +** sqlite3_backup_step(), the source database may be modified mid-way +** through the backup process. ^If the source database is modified by an +** external process or via a database connection other than the one being +** used by the backup operation, then the backup will be automatically +** restarted by the next call to sqlite3_backup_step(). ^If the source +** database is modified by the using the same database connection as is used +** by the backup operation, then the backup database is automatically +** updated at the same time. +** +** [[sqlite3_backup_finish()]] sqlite3_backup_finish() +** +** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the +** application wishes to abandon the backup operation, the application +** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). +** ^The sqlite3_backup_finish() interfaces releases all +** resources associated with the [sqlite3_backup] object. +** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any +** active write-transaction on the destination database is rolled back. +** The [sqlite3_backup] object is invalid +** and may not be used following a call to sqlite3_backup_finish(). +** +** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no +** sqlite3_backup_step() errors occurred, regardless or whether or not +** sqlite3_backup_step() completed. +** ^If an out-of-memory condition or IO error occurred during any prior +** sqlite3_backup_step() call on the same [sqlite3_backup] object, then +** sqlite3_backup_finish() returns the corresponding [error code]. +** +** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() +** is not a permanent error and does not affect the return value of +** sqlite3_backup_finish(). +** +** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] +** sqlite3_backup_remaining() and sqlite3_backup_pagecount() +** +** ^The sqlite3_backup_remaining() routine returns the number of pages still +** to be backed up at the conclusion of the most recent sqlite3_backup_step(). +** ^The sqlite3_backup_pagecount() routine returns the total number of pages +** in the source database at the conclusion of the most recent +** sqlite3_backup_step(). +** ^(The values returned by these functions are only updated by +** sqlite3_backup_step(). If the source database is modified in a way that +** changes the size of the source database or the number of pages remaining, +** those changes are not reflected in the output of sqlite3_backup_pagecount() +** and sqlite3_backup_remaining() until after the next +** sqlite3_backup_step().)^ +** +** Concurrent Usage of Database Handles +** +** ^The source [database connection] may be used by the application for other +** purposes while a backup operation is underway or being initialized. +** ^If SQLite is compiled and configured to support threadsafe database +** connections, then the source database connection may be used concurrently +** from within other threads. +** +** However, the application must guarantee that the destination +** [database connection] is not passed to any other API (by any thread) after +** sqlite3_backup_init() is called and before the corresponding call to +** sqlite3_backup_finish(). SQLite does not currently check to see +** if the application incorrectly accesses the destination [database connection] +** and so no error code is reported, but the operations may malfunction +** nevertheless. Use of the destination database connection while a +** backup is in progress might also cause a mutex deadlock. +** +** If running in [shared cache mode], the application must +** guarantee that the shared cache used by the destination database +** is not accessed while the backup is running. In practice this means +** that the application must guarantee that the disk file being +** backed up to is not accessed by any connection within the process, +** not just the specific connection that was passed to sqlite3_backup_init(). +** +** The [sqlite3_backup] object itself is partially threadsafe. Multiple +** threads may safely make multiple concurrent calls to sqlite3_backup_step(). +** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() +** APIs are not strictly speaking threadsafe. If they are invoked at the +** same time as another thread is invoking sqlite3_backup_step() it is +** possible that they return invalid values. +*/ +SQLITE_API sqlite3_backup *sqlite3_backup_init( + sqlite3 *pDest, /* Destination database handle */ + const char *zDestName, /* Destination database name */ + sqlite3 *pSource, /* Source database handle */ + const char *zSourceName /* Source database name */ +); +SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); +SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); +SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); +SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); + +/* +** CAPI3REF: Unlock Notification +** METHOD: sqlite3 +** +** ^When running in shared-cache mode, a database operation may fail with +** an [SQLITE_LOCKED] error if the required locks on the shared-cache or +** individual tables within the shared-cache cannot be obtained. See +** [SQLite Shared-Cache Mode] for a description of shared-cache locking. +** ^This API may be used to register a callback that SQLite will invoke +** when the connection currently holding the required lock relinquishes it. +** ^This API is only available if the library was compiled with the +** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. +** +** See Also: [Using the SQLite Unlock Notification Feature]. +** +** ^Shared-cache locks are released when a database connection concludes +** its current transaction, either by committing it or rolling it back. +** +** ^When a connection (known as the blocked connection) fails to obtain a +** shared-cache lock and SQLITE_LOCKED is returned to the caller, the +** identity of the database connection (the blocking connection) that +** has locked the required resource is stored internally. ^After an +** application receives an SQLITE_LOCKED error, it may call the +** sqlite3_unlock_notify() method with the blocked connection handle as +** the first argument to register for a callback that will be invoked +** when the blocking connections current transaction is concluded. ^The +** callback is invoked from within the [sqlite3_step] or [sqlite3_close] +** call that concludes the blocking connection's transaction. +** +** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, +** there is a chance that the blocking connection will have already +** concluded its transaction by the time sqlite3_unlock_notify() is invoked. +** If this happens, then the specified callback is invoked immediately, +** from within the call to sqlite3_unlock_notify().)^ +** +** ^If the blocked connection is attempting to obtain a write-lock on a +** shared-cache table, and more than one other connection currently holds +** a read-lock on the same table, then SQLite arbitrarily selects one of +** the other connections to use as the blocking connection. +** +** ^(There may be at most one unlock-notify callback registered by a +** blocked connection. If sqlite3_unlock_notify() is called when the +** blocked connection already has a registered unlock-notify callback, +** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is +** called with a NULL pointer as its second argument, then any existing +** unlock-notify callback is canceled. ^The blocked connections +** unlock-notify callback may also be canceled by closing the blocked +** connection using [sqlite3_close()]. +** +** The unlock-notify callback is not reentrant. If an application invokes +** any sqlite3_xxx API functions from within an unlock-notify callback, a +** crash or deadlock may be the result. +** +** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always +** returns SQLITE_OK. +** +** Callback Invocation Details +** +** When an unlock-notify callback is registered, the application provides a +** single void* pointer that is passed to the callback when it is invoked. +** However, the signature of the callback function allows SQLite to pass +** it an array of void* context pointers. The first argument passed to +** an unlock-notify callback is a pointer to an array of void* pointers, +** and the second is the number of entries in the array. +** +** When a blocking connection's transaction is concluded, there may be +** more than one blocked connection that has registered for an unlock-notify +** callback. ^If two or more such blocked connections have specified the +** same callback function, then instead of invoking the callback function +** multiple times, it is invoked once with the set of void* context pointers +** specified by the blocked connections bundled together into an array. +** This gives the application an opportunity to prioritize any actions +** related to the set of unblocked database connections. +** +** Deadlock Detection +** +** Assuming that after registering for an unlock-notify callback a +** database waits for the callback to be issued before taking any further +** action (a reasonable assumption), then using this API may cause the +** application to deadlock. For example, if connection X is waiting for +** connection Y's transaction to be concluded, and similarly connection +** Y is waiting on connection X's transaction, then neither connection +** will proceed and the system may remain deadlocked indefinitely. +** +** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock +** detection. ^If a given call to sqlite3_unlock_notify() would put the +** system in a deadlocked state, then SQLITE_LOCKED is returned and no +** unlock-notify callback is registered. The system is said to be in +** a deadlocked state if connection A has registered for an unlock-notify +** callback on the conclusion of connection B's transaction, and connection +** B has itself registered for an unlock-notify callback when connection +** A's transaction is concluded. ^Indirect deadlock is also detected, so +** the system is also considered to be deadlocked if connection B has +** registered for an unlock-notify callback on the conclusion of connection +** C's transaction, where connection C is waiting on connection A. ^Any +** number of levels of indirection are allowed. +** +** The "DROP TABLE" Exception +** +** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost +** always appropriate to call sqlite3_unlock_notify(). There is however, +** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, +** SQLite checks if there are any currently executing SELECT statements +** that belong to the same connection. If there are, SQLITE_LOCKED is +** returned. In this case there is no "blocking connection", so invoking +** sqlite3_unlock_notify() results in the unlock-notify callback being +** invoked immediately. If the application then re-attempts the "DROP TABLE" +** or "DROP INDEX" query, an infinite loop might be the result. +** +** One way around this problem is to check the extended error code returned +** by an sqlite3_step() call. ^(If there is a blocking connection, then the +** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in +** the special "DROP TABLE/INDEX" case, the extended error code is just +** SQLITE_LOCKED.)^ +*/ +SQLITE_API int sqlite3_unlock_notify( + sqlite3 *pBlocked, /* Waiting connection */ + void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ + void *pNotifyArg /* Argument to pass to xNotify */ +); + + +/* +** CAPI3REF: String Comparison +** +** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications +** and extensions to compare the contents of two buffers containing UTF-8 +** strings in a case-independent fashion, using the same definition of "case +** independence" that SQLite uses internally when comparing identifiers. +*/ +SQLITE_API int sqlite3_stricmp(const char *, const char *); +SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); + +/* +** CAPI3REF: String Globbing +* +** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if +** string X matches the [GLOB] pattern P. +** ^The definition of [GLOB] pattern matching used in +** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the +** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function +** is case sensitive. +** +** Note that this routine returns zero on a match and non-zero if the strings +** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. +** +** See also: [sqlite3_strlike()]. +*/ +SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); + +/* +** CAPI3REF: String LIKE Matching +* +** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if +** string X matches the [LIKE] pattern P with escape character E. +** ^The definition of [LIKE] pattern matching used in +** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" +** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without +** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. +** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case +** insensitive - equivalent upper and lower case ASCII characters match +** one another. +** +** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though +** only ASCII characters are case folded. +** +** Note that this routine returns zero on a match and non-zero if the strings +** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. +** +** See also: [sqlite3_strglob()]. +*/ +SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); + +/* +** CAPI3REF: Error Logging Interface +** +** ^The [sqlite3_log()] interface writes a message into the [error log] +** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. +** ^If logging is enabled, the zFormat string and subsequent arguments are +** used with [sqlite3_snprintf()] to generate the final output string. +** +** The sqlite3_log() interface is intended for use by extensions such as +** virtual tables, collating functions, and SQL functions. While there is +** nothing to prevent an application from calling sqlite3_log(), doing so +** is considered bad form. +** +** The zFormat string must not be NULL. +** +** To avoid deadlocks and other threading problems, the sqlite3_log() routine +** will not use dynamically allocated memory. The log message is stored in +** a fixed-length buffer on the stack. If the log message is longer than +** a few hundred characters, it will be truncated to the length of the +** buffer. +*/ +SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); + +/* +** CAPI3REF: Write-Ahead Log Commit Hook +** METHOD: sqlite3 +** +** ^The [sqlite3_wal_hook()] function is used to register a callback that +** is invoked each time data is committed to a database in wal mode. +** +** ^(The callback is invoked by SQLite after the commit has taken place and +** the associated write-lock on the database released)^, so the implementation +** may read, write or [checkpoint] the database as required. +** +** ^The first parameter passed to the callback function when it is invoked +** is a copy of the third parameter passed to sqlite3_wal_hook() when +** registering the callback. ^The second is a copy of the database handle. +** ^The third parameter is the name of the database that was written to - +** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter +** is the number of pages currently in the write-ahead log file, +** including those that were just committed. +** +** The callback function should normally return [SQLITE_OK]. ^If an error +** code is returned, that error will propagate back up through the +** SQLite code base to cause the statement that provoked the callback +** to report an error, though the commit will have still occurred. If the +** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value +** that does not correspond to any valid SQLite error code, the results +** are undefined. +** +** A single database handle may have at most a single write-ahead log callback +** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any +** previously registered write-ahead log callback. ^The return value is +** a copy of the third parameter from the previous call, if any, or 0. +** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the +** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will +** overwrite any prior [sqlite3_wal_hook()] settings. +*/ +SQLITE_API void *sqlite3_wal_hook( + sqlite3*, + int(*)(void *,sqlite3*,const char*,int), + void* +); + +/* +** CAPI3REF: Configure an auto-checkpoint +** METHOD: sqlite3 +** +** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around +** [sqlite3_wal_hook()] that causes any database on [database connection] D +** to automatically [checkpoint] +** after committing a transaction if there are N or +** more frames in the [write-ahead log] file. ^Passing zero or +** a negative value as the nFrame parameter disables automatic +** checkpoints entirely. +** +** ^The callback registered by this function replaces any existing callback +** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback +** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism +** configured by this function. +** +** ^The [wal_autocheckpoint pragma] can be used to invoke this interface +** from SQL. +** +** ^Checkpoints initiated by this mechanism are +** [sqlite3_wal_checkpoint_v2|PASSIVE]. +** +** ^Every new [database connection] defaults to having the auto-checkpoint +** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] +** pages. The use of this interface +** is only necessary if the default setting is found to be suboptimal +** for a particular application. +*/ +SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); + +/* +** CAPI3REF: Checkpoint a database +** METHOD: sqlite3 +** +** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to +** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ +** +** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the +** [write-ahead log] for database X on [database connection] D to be +** transferred into the database file and for the write-ahead log to +** be reset. See the [checkpointing] documentation for addition +** information. +** +** This interface used to be the only way to cause a checkpoint to +** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] +** interface was added. This interface is retained for backwards +** compatibility and as a convenience for applications that need to manually +** start a callback but which do not need the full power (and corresponding +** complication) of [sqlite3_wal_checkpoint_v2()]. +*/ +SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); + +/* +** CAPI3REF: Checkpoint a database +** METHOD: sqlite3 +** +** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint +** operation on database X of [database connection] D in mode M. Status +** information is written back into integers pointed to by L and C.)^ +** ^(The M parameter must be a valid [checkpoint mode]:)^ +** +**
+**
SQLITE_CHECKPOINT_PASSIVE
+** ^Checkpoint as many frames as possible without waiting for any database +** readers or writers to finish, then sync the database file if all frames +** in the log were checkpointed. ^The [busy-handler callback] +** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. +** ^On the other hand, passive mode might leave the checkpoint unfinished +** if there are concurrent readers or writers. +** +**
SQLITE_CHECKPOINT_FULL
+** ^This mode blocks (it invokes the +** [sqlite3_busy_handler|busy-handler callback]) until there is no +** database writer and all readers are reading from the most recent database +** snapshot. ^It then checkpoints all frames in the log file and syncs the +** database file. ^This mode blocks new database writers while it is pending, +** but new database readers are allowed to continue unimpeded. +** +**
SQLITE_CHECKPOINT_RESTART
+** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition +** that after checkpointing the log file it blocks (calls the +** [busy-handler callback]) +** until all readers are reading from the database file only. ^This ensures +** that the next writer will restart the log file from the beginning. +** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new +** database writer attempts while it is pending, but does not impede readers. +** +**
SQLITE_CHECKPOINT_TRUNCATE
+** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the +** addition that it also truncates the log file to zero bytes just prior +** to a successful return. +**
+** +** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in +** the log file or to -1 if the checkpoint could not run because +** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not +** NULL,then *pnCkpt is set to the total number of checkpointed frames in the +** log file (including any that were already checkpointed before the function +** was called) or to -1 if the checkpoint could not run due to an error or +** because the database is not in WAL mode. ^Note that upon successful +** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been +** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. +** +** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If +** any other process is running a checkpoint operation at the same time, the +** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a +** busy-handler configured, it will not be invoked in this case. +** +** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the +** exclusive "writer" lock on the database file. ^If the writer lock cannot be +** obtained immediately, and a busy-handler is configured, it is invoked and +** the writer lock retried until either the busy-handler returns 0 or the lock +** is successfully obtained. ^The busy-handler is also invoked while waiting for +** database readers as described above. ^If the busy-handler returns 0 before +** the writer lock is obtained or while waiting for database readers, the +** checkpoint operation proceeds from that point in the same way as +** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible +** without blocking any further. ^SQLITE_BUSY is returned in this case. +** +** ^If parameter zDb is NULL or points to a zero length string, then the +** specified operation is attempted on all WAL databases [attached] to +** [database connection] db. In this case the +** values written to output parameters *pnLog and *pnCkpt are undefined. ^If +** an SQLITE_BUSY error is encountered when processing one or more of the +** attached WAL databases, the operation is still attempted on any remaining +** attached databases and SQLITE_BUSY is returned at the end. ^If any other +** error occurs while processing an attached database, processing is abandoned +** and the error code is returned to the caller immediately. ^If no error +** (SQLITE_BUSY or otherwise) is encountered while processing the attached +** databases, SQLITE_OK is returned. +** +** ^If database zDb is the name of an attached database that is not in WAL +** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If +** zDb is not NULL (or a zero length string) and is not the name of any +** attached database, SQLITE_ERROR is returned to the caller. +** +** ^Unless it returns SQLITE_MISUSE, +** the sqlite3_wal_checkpoint_v2() interface +** sets the error information that is queried by +** [sqlite3_errcode()] and [sqlite3_errmsg()]. +** +** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface +** from SQL. +*/ +SQLITE_API int sqlite3_wal_checkpoint_v2( + sqlite3 *db, /* Database handle */ + const char *zDb, /* Name of attached database (or NULL) */ + int eMode, /* SQLITE_CHECKPOINT_* value */ + int *pnLog, /* OUT: Size of WAL log in frames */ + int *pnCkpt /* OUT: Total number of frames checkpointed */ +); + +/* +** CAPI3REF: Checkpoint Mode Values +** KEYWORDS: {checkpoint mode} +** +** These constants define all valid values for the "checkpoint mode" passed +** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. +** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the +** meaning of each of these checkpoint modes. +*/ +#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ +#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ +#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */ +#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ + +/* +** CAPI3REF: Virtual Table Interface Configuration +** +** This function may be called by either the [xConnect] or [xCreate] method +** of a [virtual table] implementation to configure +** various facets of the virtual table interface. +** +** If this interface is invoked outside the context of an xConnect or +** xCreate virtual table method then the behavior is undefined. +** +** In the call sqlite3_vtab_config(D,C,...) the D parameter is the +** [database connection] in which the virtual table is being created and +** which is passed in as the first argument to the [xConnect] or [xCreate] +** method that is invoking sqlite3_vtab_config(). The C parameter is one +** of the [virtual table configuration options]. The presence and meaning +** of parameters after C depend on which [virtual table configuration option] +** is used. +*/ +SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); + +/* +** CAPI3REF: Virtual Table Configuration Options +** KEYWORDS: {virtual table configuration options} +** KEYWORDS: {virtual table configuration option} +** +** These macros define the various options to the +** [sqlite3_vtab_config()] interface that [virtual table] implementations +** can use to customize and optimize their behavior. +** +**
+** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] +**
SQLITE_VTAB_CONSTRAINT_SUPPORT
+**
Calls of the form +** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, +** where X is an integer. If X is zero, then the [virtual table] whose +** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not +** support constraints. In this configuration (which is the default) if +** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire +** statement is rolled back as if [ON CONFLICT | OR ABORT] had been +** specified as part of the users SQL statement, regardless of the actual +** ON CONFLICT mode specified. +** +** If X is non-zero, then the virtual table implementation guarantees +** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before +** any modifications to internal or persistent data structures have been made. +** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite +** is able to roll back a statement or database transaction, and abandon +** or continue processing the current SQL statement as appropriate. +** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns +** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode +** had been ABORT. +** +** Virtual table implementations that are required to handle OR REPLACE +** must do so within the [xUpdate] method. If a call to the +** [sqlite3_vtab_on_conflict()] function indicates that the current ON +** CONFLICT policy is REPLACE, the virtual table implementation should +** silently replace the appropriate rows within the xUpdate callback and +** return SQLITE_OK. Or, if this is not possible, it may return +** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT +** constraint handling. +**
+** +** [[SQLITE_VTAB_DIRECTONLY]]
SQLITE_VTAB_DIRECTONLY
+**
Calls of the form +** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the +** the [xConnect] or [xCreate] methods of a [virtual table] implementation +** prohibits that virtual table from being used from within triggers and +** views. +**
+** +** [[SQLITE_VTAB_INNOCUOUS]]
SQLITE_VTAB_INNOCUOUS
+**
Calls of the form +** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the +** the [xConnect] or [xCreate] methods of a [virtual table] implementation +** identify that virtual table as being safe to use from within triggers +** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the +** virtual table can do no serious harm even if it is controlled by a +** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS +** flag unless absolutely necessary. +**
+** +** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]
SQLITE_VTAB_USES_ALL_SCHEMAS
+**
Calls of the form +** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the +** the [xConnect] or [xCreate] methods of a [virtual table] implementation +** instruct the query planner to begin at least a read transaction on +** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the +** virtual table is used. +**
+**
+*/ +#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 +#define SQLITE_VTAB_INNOCUOUS 2 +#define SQLITE_VTAB_DIRECTONLY 3 +#define SQLITE_VTAB_USES_ALL_SCHEMAS 4 + +/* +** CAPI3REF: Determine The Virtual Table Conflict Policy +** +** This function may only be called from within a call to the [xUpdate] method +** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The +** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], +** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode +** of the SQL statement that triggered the call to the [xUpdate] method of the +** [virtual table]. +*/ +SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); + +/* +** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE +** +** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] +** method of a [virtual table], then it might return true if the +** column is being fetched as part of an UPDATE operation during which the +** column value will not change. The virtual table implementation can use +** this hint as permission to substitute a return value that is less +** expensive to compute and that the corresponding +** [xUpdate] method understands as a "no-change" value. +** +** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that +** the column is not changed by the UPDATE statement, then the xColumn +** method can optionally return without setting a result, without calling +** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. +** In that case, [sqlite3_value_nochange(X)] will return true for the +** same column in the [xUpdate] method. +** +** The sqlite3_vtab_nochange() routine is an optimization. Virtual table +** implementations should continue to give a correct answer even if the +** sqlite3_vtab_nochange() interface were to always return false. In the +** current implementation, the sqlite3_vtab_nochange() interface does always +** returns false for the enhanced [UPDATE FROM] statement. +*/ +SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); + +/* +** CAPI3REF: Determine The Collation For a Virtual Table Constraint +** METHOD: sqlite3_index_info +** +** This function may only be called from within a call to the [xBestIndex] +** method of a [virtual table]. This function returns a pointer to a string +** that is the name of the appropriate collation sequence to use for text +** comparisons on the constraint identified by its arguments. +** +** The first argument must be the pointer to the [sqlite3_index_info] object +** that is the first parameter to the xBestIndex() method. The second argument +** must be an index into the aConstraint[] array belonging to the +** sqlite3_index_info structure passed to xBestIndex. +** +** Important: +** The first parameter must be the same pointer that is passed into the +** xBestMethod() method. The first parameter may not be a pointer to a +** different [sqlite3_index_info] object, even an exact copy. +** +** The return value is computed as follows: +** +**
    +**

  1. If the constraint comes from a WHERE clause expression that contains +** a [COLLATE operator], then the name of the collation specified by +** that COLLATE operator is returned. +**

  2. If there is no COLLATE operator, but the column that is the subject +** of the constraint specifies an alternative collating sequence via +** a [COLLATE clause] on the column definition within the CREATE TABLE +** statement that was passed into [sqlite3_declare_vtab()], then the +** name of that alternative collating sequence is returned. +**

  3. Otherwise, "BINARY" is returned. +**

+*/ +SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int); + +/* +** CAPI3REF: Determine if a virtual table query is DISTINCT +** METHOD: sqlite3_index_info +** +** This API may only be used from within an [xBestIndex|xBestIndex method] +** of a [virtual table] implementation. The result of calling this +** interface from outside of xBestIndex() is undefined and probably harmful. +** +** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and +** 3. The integer returned by sqlite3_vtab_distinct() +** gives the virtual table additional information about how the query +** planner wants the output to be ordered. As long as the virtual table +** can meet the ordering requirements of the query planner, it may set +** the "orderByConsumed" flag. +** +**

  1. +** ^If the sqlite3_vtab_distinct() interface returns 0, that means +** that the query planner needs the virtual table to return all rows in the +** sort order defined by the "nOrderBy" and "aOrderBy" fields of the +** [sqlite3_index_info] object. This is the default expectation. If the +** virtual table outputs all rows in sorted order, then it is always safe for +** the xBestIndex method to set the "orderByConsumed" flag, regardless of +** the return value from sqlite3_vtab_distinct(). +**

  2. +** ^(If the sqlite3_vtab_distinct() interface returns 1, that means +** that the query planner does not need the rows to be returned in sorted order +** as long as all rows with the same values in all columns identified by the +** "aOrderBy" field are adjacent.)^ This mode is used when the query planner +** is doing a GROUP BY. +**

  3. +** ^(If the sqlite3_vtab_distinct() interface returns 2, that means +** that the query planner does not need the rows returned in any particular +** order, as long as rows with the same values in all columns identified +** by "aOrderBy" are adjacent.)^ ^(Furthermore, when two or more rows +** contain the same values for all columns identified by "colUsed", all but +** one such row may optionally be omitted from the result.)^ +** The virtual table is not required to omit rows that are duplicates +** over the "colUsed" columns, but if the virtual table can do that without +** too much extra effort, it could potentially help the query to run faster. +** This mode is used for a DISTINCT query. +**

  4. +** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the +** virtual table must return rows in the order defined by "aOrderBy" as +** if the sqlite3_vtab_distinct() interface had returned 0. However if +** two or more rows in the result have the same values for all columns +** identified by "colUsed", then all but one such row may optionally be +** omitted.)^ Like when the return value is 2, the virtual table +** is not required to omit rows that are duplicates over the "colUsed" +** columns, but if the virtual table can do that without +** too much extra effort, it could potentially help the query to run faster. +** This mode is used for queries +** that have both DISTINCT and ORDER BY clauses. +**

+** +**

The following table summarizes the conditions under which the +** virtual table is allowed to set the "orderByConsumed" flag based on +** the value returned by sqlite3_vtab_distinct(). This table is a +** restatement of the previous four paragraphs: +** +** +** +**
sqlite3_vtab_distinct() return value +** Rows are returned in aOrderBy order +** Rows with the same value in all aOrderBy columns are adjacent +** Duplicates over all colUsed columns may be omitted +**
0yesyesno +**
1noyesno +**
2noyesyes +**
3yesyesyes +**
+** +** ^For the purposes of comparing virtual table output values to see if the +** values are same value for sorting purposes, two NULL values are considered +** to be the same. In other words, the comparison operator is "IS" +** (or "IS NOT DISTINCT FROM") and not "==". +** +** If a virtual table implementation is unable to meet the requirements +** specified above, then it must not set the "orderByConsumed" flag in the +** [sqlite3_index_info] object or an incorrect answer may result. +** +** ^A virtual table implementation is always free to return rows in any order +** it wants, as long as the "orderByConsumed" flag is not set. ^When the +** the "orderByConsumed" flag is unset, the query planner will add extra +** [bytecode] to ensure that the final results returned by the SQL query are +** ordered correctly. The use of the "orderByConsumed" flag and the +** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful +** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed" +** flag might help queries against a virtual table to run faster. Being +** overly aggressive and setting the "orderByConsumed" flag when it is not +** valid to do so, on the other hand, might cause SQLite to return incorrect +** results. +*/ +SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*); + +/* +** CAPI3REF: Identify and handle IN constraints in xBestIndex +** +** This interface may only be used from within an +** [xBestIndex|xBestIndex() method] of a [virtual table] implementation. +** The result of invoking this interface from any other context is +** undefined and probably harmful. +** +** ^(A constraint on a virtual table of the form +** "[IN operator|column IN (...)]" is +** communicated to the xBestIndex method as a +** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use +** this constraint, it must set the corresponding +** aConstraintUsage[].argvIndex to a positive integer. ^(Then, under +** the usual mode of handling IN operators, SQLite generates [bytecode] +** that invokes the [xFilter|xFilter() method] once for each value +** on the right-hand side of the IN operator.)^ Thus the virtual table +** only sees a single value from the right-hand side of the IN operator +** at a time. +** +** In some cases, however, it would be advantageous for the virtual +** table to see all values on the right-hand of the IN operator all at +** once. The sqlite3_vtab_in() interfaces facilitates this in two ways: +** +**

    +**

  1. +** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero) +** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint +** is an [IN operator] that can be processed all at once. ^In other words, +** sqlite3_vtab_in() with -1 in the third argument is a mechanism +** by which the virtual table can ask SQLite if all-at-once processing +** of the IN operator is even possible. +** +**

  2. +** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates +** to SQLite that the virtual table does or does not want to process +** the IN operator all-at-once, respectively. ^Thus when the third +** parameter (F) is non-negative, this interface is the mechanism by +** which the virtual table tells SQLite how it wants to process the +** IN operator. +**

+** +** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times +** within the same xBestIndex method call. ^For any given P,N pair, +** the return value from sqlite3_vtab_in(P,N,F) will always be the same +** within the same xBestIndex call. ^If the interface returns true +** (non-zero), that means that the constraint is an IN operator +** that can be processed all-at-once. ^If the constraint is not an IN +** operator or cannot be processed all-at-once, then the interface returns +** false. +** +** ^(All-at-once processing of the IN operator is selected if both of the +** following conditions are met: +** +**
    +**

  1. The P->aConstraintUsage[N].argvIndex value is set to a positive +** integer. This is how the virtual table tells SQLite that it wants to +** use the N-th constraint. +** +**

  2. The last call to sqlite3_vtab_in(P,N,F) for which F was +** non-negative had F>=1. +**

)^ +** +** ^If either or both of the conditions above are false, then SQLite uses +** the traditional one-at-a-time processing strategy for the IN constraint. +** ^If both conditions are true, then the argvIndex-th parameter to the +** xFilter method will be an [sqlite3_value] that appears to be NULL, +** but which can be passed to [sqlite3_vtab_in_first()] and +** [sqlite3_vtab_in_next()] to find all values on the right-hand side +** of the IN constraint. +*/ +SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle); + +/* +** CAPI3REF: Find all elements on the right-hand side of an IN constraint. +** +** These interfaces are only useful from within the +** [xFilter|xFilter() method] of a [virtual table] implementation. +** The result of invoking these interfaces from any other context +** is undefined and probably harmful. +** +** The X parameter in a call to sqlite3_vtab_in_first(X,P) or +** sqlite3_vtab_in_next(X,P) should be one of the parameters to the +** xFilter method which invokes these routines, and specifically +** a parameter that was previously selected for all-at-once IN constraint +** processing use the [sqlite3_vtab_in()] interface in the +** [xBestIndex|xBestIndex method]. ^(If the X parameter is not +** an xFilter argument that was selected for all-at-once IN constraint +** processing, then these routines return [SQLITE_ERROR].)^ +** +** ^(Use these routines to access all values on the right-hand side +** of the IN constraint using code like the following: +** +** 
+**    for(rc=sqlite3_vtab_in_first(pList, &pVal);
+**        rc==SQLITE_OK && pVal;
+**        rc=sqlite3_vtab_in_next(pList, &pVal)
+**    ){
+**      // do something with pVal
+**    }
+**    if( rc!=SQLITE_OK ){
+**      // an error has occurred
+**    }
+**
)^ +** +** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P) +** routines return SQLITE_OK and set *P to point to the first or next value +** on the RHS of the IN constraint. ^If there are no more values on the +** right hand side of the IN constraint, then *P is set to NULL and these +** routines return [SQLITE_DONE]. ^The return value might be +** some other value, such as SQLITE_NOMEM, in the event of a malfunction. +** +** The *ppOut values returned by these routines are only valid until the +** next call to either of these routines or until the end of the xFilter +** method from which these routines were called. If the virtual table +** implementation needs to retain the *ppOut values for longer, it must make +** copies. The *ppOut values are [protected sqlite3_value|protected]. +*/ +SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut); +SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut); + +/* +** CAPI3REF: Constraint values in xBestIndex() +** METHOD: sqlite3_index_info +** +** This API may only be used from within the [xBestIndex|xBestIndex method] +** of a [virtual table] implementation. The result of calling this interface +** from outside of an xBestIndex method are undefined and probably harmful. +** +** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within +** the [xBestIndex] method of a [virtual table] implementation, with P being +** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and +** J being a 0-based index into P->aConstraint[], then this routine +** attempts to set *V to the value of the right-hand operand of +** that constraint if the right-hand operand is known. ^If the +** right-hand operand is not known, then *V is set to a NULL pointer. +** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if +** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V) +** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th +** constraint is not available. ^The sqlite3_vtab_rhs_value() interface +** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if +** something goes wrong. +** +** The sqlite3_vtab_rhs_value() interface is usually only successful if +** the right-hand operand of a constraint is a literal value in the original +** SQL statement. If the right-hand operand is an expression or a reference +** to some other column or a [host parameter], then sqlite3_vtab_rhs_value() +** will probably return [SQLITE_NOTFOUND]. +** +** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and +** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such +** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^ +** +** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value +** and remains valid for the duration of the xBestIndex method call. +** ^When xBestIndex returns, the sqlite3_value object returned by +** sqlite3_vtab_rhs_value() is automatically deallocated. +** +** The "_rhs_" in the name of this routine is an abbreviation for +** "Right-Hand Side". +*/ +SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal); + +/* +** CAPI3REF: Conflict resolution modes +** KEYWORDS: {conflict resolution mode} +** +** These constants are returned by [sqlite3_vtab_on_conflict()] to +** inform a [virtual table] implementation what the [ON CONFLICT] mode +** is for the SQL statement being evaluated. +** +** Note that the [SQLITE_IGNORE] constant is also used as a potential +** return value from the [sqlite3_set_authorizer()] callback and that +** [SQLITE_ABORT] is also a [result code]. +*/ +#define SQLITE_ROLLBACK 1 +/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ +#define SQLITE_FAIL 3 +/* #define SQLITE_ABORT 4 // Also an error code */ +#define SQLITE_REPLACE 5 + +/* +** CAPI3REF: Prepared Statement Scan Status Opcodes +** KEYWORDS: {scanstatus options} +** +** The following constants can be used for the T parameter to the +** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a +** different metric for sqlite3_stmt_scanstatus() to return. +** +** When the value returned to V is a string, space to hold that string is +** managed by the prepared statement S and will be automatically freed when +** S is finalized. +** +** Not all values are available for all query elements. When a value is +** not available, the output variable is set to -1 if the value is numeric, +** or to NULL if it is a string (SQLITE_SCANSTAT_NAME). +** +**
+** [[SQLITE_SCANSTAT_NLOOP]]
SQLITE_SCANSTAT_NLOOP
+**
^The [sqlite3_int64] variable pointed to by the V parameter will be +** set to the total number of times that the X-th loop has run.
+** +** [[SQLITE_SCANSTAT_NVISIT]]
SQLITE_SCANSTAT_NVISIT
+**
^The [sqlite3_int64] variable pointed to by the V parameter will be set +** to the total number of rows examined by all iterations of the X-th loop.
+** +** [[SQLITE_SCANSTAT_EST]]
SQLITE_SCANSTAT_EST
+**
^The "double" variable pointed to by the V parameter will be set to the +** query planner's estimate for the average number of rows output from each +** iteration of the X-th loop. If the query planner's estimates was accurate, +** then this value will approximate the quotient NVISIT/NLOOP and the +** product of this value for all prior loops with the same SELECTID will +** be the NLOOP value for the current loop. +** +** [[SQLITE_SCANSTAT_NAME]]
SQLITE_SCANSTAT_NAME
+**
^The "const char *" variable pointed to by the V parameter will be set +** to a zero-terminated UTF-8 string containing the name of the index or table +** used for the X-th loop. +** +** [[SQLITE_SCANSTAT_EXPLAIN]]
SQLITE_SCANSTAT_EXPLAIN
+**
^The "const char *" variable pointed to by the V parameter will be set +** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] +** description for the X-th loop. +** +** [[SQLITE_SCANSTAT_SELECTID]]
SQLITE_SCANSTAT_SELECTID
+**
^The "int" variable pointed to by the V parameter will be set to the +** id for the X-th query plan element. The id value is unique within the +** statement. The select-id is the same value as is output in the first +** column of an [EXPLAIN QUERY PLAN] query. +** +** [[SQLITE_SCANSTAT_PARENTID]]
SQLITE_SCANSTAT_PARENTID
+**
The "int" variable pointed to by the V parameter will be set to the +** the id of the parent of the current query element, if applicable, or +** to zero if the query element has no parent. This is the same value as +** returned in the second column of an [EXPLAIN QUERY PLAN] query. +** +** [[SQLITE_SCANSTAT_NCYCLE]]
SQLITE_SCANSTAT_NCYCLE
+**
The sqlite3_int64 output value is set to the number of cycles, +** according to the processor time-stamp counter, that elapsed while the +** query element was being processed. This value is not available for +** all query elements - if it is unavailable the output variable is +** set to -1. +**
+*/ +#define SQLITE_SCANSTAT_NLOOP 0 +#define SQLITE_SCANSTAT_NVISIT 1 +#define SQLITE_SCANSTAT_EST 2 +#define SQLITE_SCANSTAT_NAME 3 +#define SQLITE_SCANSTAT_EXPLAIN 4 +#define SQLITE_SCANSTAT_SELECTID 5 +#define SQLITE_SCANSTAT_PARENTID 6 +#define SQLITE_SCANSTAT_NCYCLE 7 + +/* +** CAPI3REF: Prepared Statement Scan Status +** METHOD: sqlite3_stmt +** +** These interfaces return information about the predicted and measured +** performance for pStmt. Advanced applications can use this +** interface to compare the predicted and the measured performance and +** issue warnings and/or rerun [ANALYZE] if discrepancies are found. +** +** Since this interface is expected to be rarely used, it is only +** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] +** compile-time option. +** +** The "iScanStatusOp" parameter determines which status information to return. +** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior +** of this interface is undefined. ^The requested measurement is written into +** a variable pointed to by the "pOut" parameter. +** +** The "flags" parameter must be passed a mask of flags. At present only +** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX +** is specified, then status information is available for all elements +** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If +** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements +** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of +** the EXPLAIN QUERY PLAN output) are available. Invoking API +** sqlite3_stmt_scanstatus() is equivalent to calling +** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter. +** +** Parameter "idx" identifies the specific query element to retrieve statistics +** for. Query elements are numbered starting from zero. A value of -1 may be +** to query for statistics regarding the entire query. ^If idx is out of range +** - less than -1 or greater than or equal to the total number of query +** elements used to implement the statement - a non-zero value is returned and +** the variable that pOut points to is unchanged. +** +** See also: [sqlite3_stmt_scanstatus_reset()] +*/ +SQLITE_API int sqlite3_stmt_scanstatus( + sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ + int idx, /* Index of loop to report on */ + int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ + void *pOut /* Result written here */ +); +SQLITE_API int sqlite3_stmt_scanstatus_v2( + sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ + int idx, /* Index of loop to report on */ + int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ + int flags, /* Mask of flags defined below */ + void *pOut /* Result written here */ +); + +/* +** CAPI3REF: Prepared Statement Scan Status +** KEYWORDS: {scan status flags} +*/ +#define SQLITE_SCANSTAT_COMPLEX 0x0001 + +/* +** CAPI3REF: Zero Scan-Status Counters +** METHOD: sqlite3_stmt +** +** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. +** +** This API is only available if the library is built with pre-processor +** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. +*/ +SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); + +/* +** CAPI3REF: Flush caches to disk mid-transaction +** METHOD: sqlite3 +** +** ^If a write-transaction is open on [database connection] D when the +** [sqlite3_db_cacheflush(D)] interface invoked, any dirty +** pages in the pager-cache that are not currently in use are written out +** to disk. A dirty page may be in use if a database cursor created by an +** active SQL statement is reading from it, or if it is page 1 of a database +** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] +** interface flushes caches for all schemas - "main", "temp", and +** any [attached] databases. +** +** ^If this function needs to obtain extra database locks before dirty pages +** can be flushed to disk, it does so. ^If those locks cannot be obtained +** immediately and there is a busy-handler callback configured, it is invoked +** in the usual manner. ^If the required lock still cannot be obtained, then +** the database is skipped and an attempt made to flush any dirty pages +** belonging to the next (if any) database. ^If any databases are skipped +** because locks cannot be obtained, but no other error occurs, this +** function returns SQLITE_BUSY. +** +** ^If any other error occurs while flushing dirty pages to disk (for +** example an IO error or out-of-memory condition), then processing is +** abandoned and an SQLite [error code] is returned to the caller immediately. +** +** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. +** +** ^This function does not set the database handle error code or message +** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. +*/ +SQLITE_API int sqlite3_db_cacheflush(sqlite3*); + +/* +** CAPI3REF: The pre-update hook. +** METHOD: sqlite3 +** +** ^These interfaces are only available if SQLite is compiled using the +** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. +** +** ^The [sqlite3_preupdate_hook()] interface registers a callback function +** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation +** on a database table. +** ^At most one preupdate hook may be registered at a time on a single +** [database connection]; each call to [sqlite3_preupdate_hook()] overrides +** the previous setting. +** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] +** with a NULL pointer as the second parameter. +** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as +** the first parameter to callbacks. +** +** ^The preupdate hook only fires for changes to real database tables; the +** preupdate hook is not invoked for changes to [virtual tables] or to +** system tables like sqlite_sequence or sqlite_stat1. +** +** ^The second parameter to the preupdate callback is a pointer to +** the [database connection] that registered the preupdate hook. +** ^The third parameter to the preupdate callback is one of the constants +** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the +** kind of update operation that is about to occur. +** ^(The fourth parameter to the preupdate callback is the name of the +** database within the database connection that is being modified. This +** will be "main" for the main database or "temp" for TEMP tables or +** the name given after the AS keyword in the [ATTACH] statement for attached +** databases.)^ +** ^The fifth parameter to the preupdate callback is the name of the +** table that is being modified. +** +** For an UPDATE or DELETE operation on a [rowid table], the sixth +** parameter passed to the preupdate callback is the initial [rowid] of the +** row being modified or deleted. For an INSERT operation on a rowid table, +** or any operation on a WITHOUT ROWID table, the value of the sixth +** parameter is undefined. For an INSERT or UPDATE on a rowid table the +** seventh parameter is the final rowid value of the row being inserted +** or updated. The value of the seventh parameter passed to the callback +** function is not defined for operations on WITHOUT ROWID tables, or for +** DELETE operations on rowid tables. +** +** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from +** the previous call on the same [database connection] D, or NULL for +** the first call on D. +** +** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], +** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces +** provide additional information about a preupdate event. These routines +** may only be called from within a preupdate callback. Invoking any of +** these routines from outside of a preupdate callback or with a +** [database connection] pointer that is different from the one supplied +** to the preupdate callback results in undefined and probably undesirable +** behavior. +** +** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns +** in the row that is being inserted, updated, or deleted. +** +** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to +** a [protected sqlite3_value] that contains the value of the Nth column of +** the table row before it is updated. The N parameter must be between 0 +** and one less than the number of columns or the behavior will be +** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE +** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the +** behavior is undefined. The [sqlite3_value] that P points to +** will be destroyed when the preupdate callback returns. +** +** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to +** a [protected sqlite3_value] that contains the value of the Nth column of +** the table row after it is updated. The N parameter must be between 0 +** and one less than the number of columns or the behavior will be +** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE +** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the +** behavior is undefined. The [sqlite3_value] that P points to +** will be destroyed when the preupdate callback returns. +** +** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate +** callback was invoked as a result of a direct insert, update, or delete +** operation; or 1 for inserts, updates, or deletes invoked by top-level +** triggers; or 2 for changes resulting from triggers called by top-level +** triggers; and so forth. +** +** When the [sqlite3_blob_write()] API is used to update a blob column, +** the pre-update hook is invoked with SQLITE_DELETE. This is because the +** in this case the new values are not available. In this case, when a +** callback made with op==SQLITE_DELETE is actually a write using the +** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns +** the index of the column being written. In other cases, where the +** pre-update hook is being invoked for some other reason, including a +** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. +** +** See also: [sqlite3_update_hook()] +*/ +#if defined(SQLITE_ENABLE_PREUPDATE_HOOK) +SQLITE_API void *sqlite3_preupdate_hook( + sqlite3 *db, + void(*xPreUpdate)( + void *pCtx, /* Copy of third arg to preupdate_hook() */ + sqlite3 *db, /* Database handle */ + int op, /* SQLITE_UPDATE, DELETE or INSERT */ + char const *zDb, /* Database name */ + char const *zName, /* Table name */ + sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ + sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ + ), + void* +); +SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); +SQLITE_API int sqlite3_preupdate_count(sqlite3 *); +SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); +SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); +SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *); +#endif + +/* +** CAPI3REF: Low-level system error code +** METHOD: sqlite3 +** +** ^Attempt to return the underlying operating system error code or error +** number that caused the most recent I/O error or failure to open a file. +** The return value is OS-dependent. For example, on unix systems, after +** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be +** called to get back the underlying "errno" that caused the problem, such +** as ENOSPC, EAUTH, EISDIR, and so forth. +*/ +SQLITE_API int sqlite3_system_errno(sqlite3*); + +/* +** CAPI3REF: Database Snapshot +** KEYWORDS: {snapshot} {sqlite3_snapshot} +** +** An instance of the snapshot object records the state of a [WAL mode] +** database for some specific point in history. +** +** In [WAL mode], multiple [database connections] that are open on the +** same database file can each be reading a different historical version +** of the database file. When a [database connection] begins a read +** transaction, that connection sees an unchanging copy of the database +** as it existed for the point in time when the transaction first started. +** Subsequent changes to the database from other connections are not seen +** by the reader until a new read transaction is started. +** +** The sqlite3_snapshot object records state information about an historical +** version of the database file so that it is possible to later open a new read +** transaction that sees that historical version of the database rather than +** the most recent version. +*/ +typedef struct sqlite3_snapshot { + unsigned char hidden[48]; +} sqlite3_snapshot; + +/* +** CAPI3REF: Record A Database Snapshot +** CONSTRUCTOR: sqlite3_snapshot +** +** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a +** new [sqlite3_snapshot] object that records the current state of +** schema S in database connection D. ^On success, the +** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly +** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. +** If there is not already a read-transaction open on schema S when +** this function is called, one is opened automatically. +** +** The following must be true for this function to succeed. If any of +** the following statements are false when sqlite3_snapshot_get() is +** called, SQLITE_ERROR is returned. The final value of *P is undefined +** in this case. +** +**
    +**
  • The database handle must not be in [autocommit mode]. +** +**
  • Schema S of [database connection] D must be a [WAL mode] database. +** +**
  • There must not be a write transaction open on schema S of database +** connection D. +** +**
  • One or more transactions must have been written to the current wal +** file since it was created on disk (by any connection). This means +** that a snapshot cannot be taken on a wal mode database with no wal +** file immediately after it is first opened. At least one transaction +** must be written to it first. +**
+** +** This function may also return SQLITE_NOMEM. If it is called with the +** database handle in autocommit mode but fails for some other reason, +** whether or not a read transaction is opened on schema S is undefined. +** +** The [sqlite3_snapshot] object returned from a successful call to +** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] +** to avoid a memory leak. +** +** The [sqlite3_snapshot_get()] interface is only available when the +** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. +*/ +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( + sqlite3 *db, + const char *zSchema, + sqlite3_snapshot **ppSnapshot +); + +/* +** CAPI3REF: Start a read transaction on an historical snapshot +** METHOD: sqlite3_snapshot +** +** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read +** transaction or upgrades an existing one for schema S of +** [database connection] D such that the read transaction refers to +** historical [snapshot] P, rather than the most recent change to the +** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK +** on success or an appropriate [error code] if it fails. +** +** ^In order to succeed, the database connection must not be in +** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there +** is already a read transaction open on schema S, then the database handle +** must have no active statements (SELECT statements that have been passed +** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). +** SQLITE_ERROR is returned if either of these conditions is violated, or +** if schema S does not exist, or if the snapshot object is invalid. +** +** ^A call to sqlite3_snapshot_open() will fail to open if the specified +** snapshot has been overwritten by a [checkpoint]. In this case +** SQLITE_ERROR_SNAPSHOT is returned. +** +** If there is already a read transaction open when this function is +** invoked, then the same read transaction remains open (on the same +** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT +** is returned. If another error code - for example SQLITE_PROTOCOL or an +** SQLITE_IOERR error code - is returned, then the final state of the +** read transaction is undefined. If SQLITE_OK is returned, then the +** read transaction is now open on database snapshot P. +** +** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the +** database connection D does not know that the database file for +** schema S is in [WAL mode]. A database connection might not know +** that the database file is in [WAL mode] if there has been no prior +** I/O on that database connection, or if the database entered [WAL mode] +** after the most recent I/O on the database connection.)^ +** (Hint: Run "[PRAGMA application_id]" against a newly opened +** database connection in order to make it ready to use snapshots.) +** +** The [sqlite3_snapshot_open()] interface is only available when the +** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. +*/ +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( + sqlite3 *db, + const char *zSchema, + sqlite3_snapshot *pSnapshot +); + +/* +** CAPI3REF: Destroy a snapshot +** DESTRUCTOR: sqlite3_snapshot +** +** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. +** The application must eventually free every [sqlite3_snapshot] object +** using this routine to avoid a memory leak. +** +** The [sqlite3_snapshot_free()] interface is only available when the +** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. +*/ +SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); + +/* +** CAPI3REF: Compare the ages of two snapshot handles. +** METHOD: sqlite3_snapshot +** +** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages +** of two valid snapshot handles. +** +** If the two snapshot handles are not associated with the same database +** file, the result of the comparison is undefined. +** +** Additionally, the result of the comparison is only valid if both of the +** snapshot handles were obtained by calling sqlite3_snapshot_get() since the +** last time the wal file was deleted. The wal file is deleted when the +** database is changed back to rollback mode or when the number of database +** clients drops to zero. If either snapshot handle was obtained before the +** wal file was last deleted, the value returned by this function +** is undefined. +** +** Otherwise, this API returns a negative value if P1 refers to an older +** snapshot than P2, zero if the two handles refer to the same database +** snapshot, and a positive value if P1 is a newer snapshot than P2. +** +** This interface is only available if SQLite is compiled with the +** [SQLITE_ENABLE_SNAPSHOT] option. +*/ +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( + sqlite3_snapshot *p1, + sqlite3_snapshot *p2 +); + +/* +** CAPI3REF: Recover snapshots from a wal file +** METHOD: sqlite3_snapshot +** +** If a [WAL file] remains on disk after all database connections close +** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] +** or because the last process to have the database opened exited without +** calling [sqlite3_close()]) and a new connection is subsequently opened +** on that database and [WAL file], the [sqlite3_snapshot_open()] interface +** will only be able to open the last transaction added to the WAL file +** even though the WAL file contains other valid transactions. +** +** This function attempts to scan the WAL file associated with database zDb +** of database handle db and make all valid snapshots available to +** sqlite3_snapshot_open(). It is an error if there is already a read +** transaction open on the database, or if the database is not a WAL mode +** database. +** +** SQLITE_OK is returned if successful, or an SQLite error code otherwise. +** +** This interface is only available if SQLite is compiled with the +** [SQLITE_ENABLE_SNAPSHOT] option. +*/ +SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); + +/* +** CAPI3REF: Serialize a database +** +** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory +** that is a serialization of the S database on [database connection] D. +** If P is not a NULL pointer, then the size of the database in bytes +** is written into *P. +** +** For an ordinary on-disk database file, the serialization is just a +** copy of the disk file. For an in-memory database or a "TEMP" database, +** the serialization is the same sequence of bytes which would be written +** to disk if that database where backed up to disk. +** +** The usual case is that sqlite3_serialize() copies the serialization of +** the database into memory obtained from [sqlite3_malloc64()] and returns +** a pointer to that memory. The caller is responsible for freeing the +** returned value to avoid a memory leak. However, if the F argument +** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations +** are made, and the sqlite3_serialize() function will return a pointer +** to the contiguous memory representation of the database that SQLite +** is currently using for that database, or NULL if the no such contiguous +** memory representation of the database exists. A contiguous memory +** representation of the database will usually only exist if there has +** been a prior call to [sqlite3_deserialize(D,S,...)] with the same +** values of D and S. +** The size of the database is written into *P even if the +** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy +** of the database exists. +** +** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set, +** the returned buffer content will remain accessible and unchanged +** until either the next write operation on the connection or when +** the connection is closed, and applications must not modify the +** buffer. If the bit had been clear, the returned buffer will not +** be accessed by SQLite after the call. +** +** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the +** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory +** allocation error occurs. +** +** This interface is omitted if SQLite is compiled with the +** [SQLITE_OMIT_DESERIALIZE] option. +*/ +SQLITE_API unsigned char *sqlite3_serialize( + sqlite3 *db, /* The database connection */ + const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ + sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ + unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ +); + +/* +** CAPI3REF: Flags for sqlite3_serialize +** +** Zero or more of the following constants can be OR-ed together for +** the F argument to [sqlite3_serialize(D,S,P,F)]. +** +** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return +** a pointer to contiguous in-memory database that it is currently using, +** without making a copy of the database. If SQLite is not currently using +** a contiguous in-memory database, then this option causes +** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be +** using a contiguous in-memory database if it has been initialized by a +** prior call to [sqlite3_deserialize()]. +*/ +#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ + +/* +** CAPI3REF: Deserialize a database +** +** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the +** [database connection] D to disconnect from database S and then +** reopen S as an in-memory database based on the serialization contained +** in P. The serialized database P is N bytes in size. M is the size of +** the buffer P, which might be larger than N. If M is larger than N, and +** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is +** permitted to add content to the in-memory database as long as the total +** size does not exceed M bytes. +** +** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will +** invoke sqlite3_free() on the serialization buffer when the database +** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then +** SQLite will try to increase the buffer size using sqlite3_realloc64() +** if writes on the database cause it to grow larger than M bytes. +** +** Applications must not modify the buffer P or invalidate it before +** the database connection D is closed. +** +** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the +** database is currently in a read transaction or is involved in a backup +** operation. +** +** It is not possible to deserialized into the TEMP database. If the +** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the +** function returns SQLITE_ERROR. +** +** The deserialized database should not be in [WAL mode]. If the database +** is in WAL mode, then any attempt to use the database file will result +** in an [SQLITE_CANTOPEN] error. The application can set the +** [file format version numbers] (bytes 18 and 19) of the input database P +** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the +** database file into rollback mode and work around this limitation. +** +** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the +** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then +** [sqlite3_free()] is invoked on argument P prior to returning. +** +** This interface is omitted if SQLite is compiled with the +** [SQLITE_OMIT_DESERIALIZE] option. +*/ +SQLITE_API int sqlite3_deserialize( + sqlite3 *db, /* The database connection */ + const char *zSchema, /* Which DB to reopen with the deserialization */ + unsigned char *pData, /* The serialized database content */ + sqlite3_int64 szDb, /* Number bytes in the deserialization */ + sqlite3_int64 szBuf, /* Total size of buffer pData[] */ + unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ +); + +/* +** CAPI3REF: Flags for sqlite3_deserialize() +** +** The following are allowed values for 6th argument (the F argument) to +** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. +** +** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization +** in the P argument is held in memory obtained from [sqlite3_malloc64()] +** and that SQLite should take ownership of this memory and automatically +** free it when it has finished using it. Without this flag, the caller +** is responsible for freeing any dynamically allocated memory. +** +** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to +** grow the size of the database using calls to [sqlite3_realloc64()]. This +** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. +** Without this flag, the deserialized database cannot increase in size beyond +** the number of bytes specified by the M parameter. +** +** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database +** should be treated as read-only. +*/ +#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ +#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ +#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ + +/* +** Undo the hack that converts floating point types to integer for +** builds on processors without floating point support. +*/ +#ifdef SQLITE_OMIT_FLOATING_POINT +# undef double +#endif + +#if defined(__wasi__) +# undef SQLITE_WASI +# define SQLITE_WASI 1 +# undef SQLITE_OMIT_WAL +# define SQLITE_OMIT_WAL 1/* because it requires shared memory APIs */ +# ifndef SQLITE_OMIT_LOAD_EXTENSION +# define SQLITE_OMIT_LOAD_EXTENSION +# endif +# ifndef SQLITE_THREADSAFE +# define SQLITE_THREADSAFE 0 +# endif +#endif + +#ifdef __cplusplus +} /* End of the 'extern "C"' block */ +#endif +#endif /* SQLITE3_H */ + +/******** Begin file sqlite3rtree.h *********/ +/* +** 2010 August 30 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +*/ + +#ifndef _SQLITE3RTREE_H_ +#define _SQLITE3RTREE_H_ + + +#ifdef __cplusplus +extern "C" { +#endif + +typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; +typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; + +/* The double-precision datatype used by RTree depends on the +** SQLITE_RTREE_INT_ONLY compile-time option. +*/ +#ifdef SQLITE_RTREE_INT_ONLY + typedef sqlite3_int64 sqlite3_rtree_dbl; +#else + typedef double sqlite3_rtree_dbl; +#endif + +/* +** Register a geometry callback named zGeom that can be used as part of an +** R-Tree geometry query as follows: +** +** SELECT ... FROM WHERE MATCH $zGeom(... params ...) +*/ +SQLITE_API int sqlite3_rtree_geometry_callback( + sqlite3 *db, + const char *zGeom, + int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), + void *pContext +); + + +/* +** A pointer to a structure of the following type is passed as the first +** argument to callbacks registered using rtree_geometry_callback(). +*/ +struct sqlite3_rtree_geometry { + void *pContext; /* Copy of pContext passed to s_r_g_c() */ + int nParam; /* Size of array aParam[] */ + sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ + void *pUser; /* Callback implementation user data */ + void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ +}; + +/* +** Register a 2nd-generation geometry callback named zScore that can be +** used as part of an R-Tree geometry query as follows: +** +** SELECT ... FROM WHERE MATCH $zQueryFunc(... params ...) +*/ +SQLITE_API int sqlite3_rtree_query_callback( + sqlite3 *db, + const char *zQueryFunc, + int (*xQueryFunc)(sqlite3_rtree_query_info*), + void *pContext, + void (*xDestructor)(void*) +); + + +/* +** A pointer to a structure of the following type is passed as the +** argument to scored geometry callback registered using +** sqlite3_rtree_query_callback(). +** +** Note that the first 5 fields of this structure are identical to +** sqlite3_rtree_geometry. This structure is a subclass of +** sqlite3_rtree_geometry. +*/ +struct sqlite3_rtree_query_info { + void *pContext; /* pContext from when function registered */ + int nParam; /* Number of function parameters */ + sqlite3_rtree_dbl *aParam; /* value of function parameters */ + void *pUser; /* callback can use this, if desired */ + void (*xDelUser)(void*); /* function to free pUser */ + sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ + unsigned int *anQueue; /* Number of pending entries in the queue */ + int nCoord; /* Number of coordinates */ + int iLevel; /* Level of current node or entry */ + int mxLevel; /* The largest iLevel value in the tree */ + sqlite3_int64 iRowid; /* Rowid for current entry */ + sqlite3_rtree_dbl rParentScore; /* Score of parent node */ + int eParentWithin; /* Visibility of parent node */ + int eWithin; /* OUT: Visibility */ + sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ + /* The following fields are only available in 3.8.11 and later */ + sqlite3_value **apSqlParam; /* Original SQL values of parameters */ +}; + +/* +** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. +*/ +#define NOT_WITHIN 0 /* Object completely outside of query region */ +#define PARTLY_WITHIN 1 /* Object partially overlaps query region */ +#define FULLY_WITHIN 2 /* Object fully contained within query region */ + + +#ifdef __cplusplus +} /* end of the 'extern "C"' block */ +#endif + +#endif /* ifndef _SQLITE3RTREE_H_ */ + +/******** End of sqlite3rtree.h *********/ +/******** Begin file sqlite3session.h *********/ + +#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) +#define __SQLITESESSION_H_ 1 + +/* +** Make sure we can call this stuff from C++. +*/ +#ifdef __cplusplus +extern "C" { +#endif + + +/* +** CAPI3REF: Session Object Handle +** +** An instance of this object is a [session] that can be used to +** record changes to a database. +*/ +typedef struct sqlite3_session sqlite3_session; + +/* +** CAPI3REF: Changeset Iterator Handle +** +** An instance of this object acts as a cursor for iterating +** over the elements of a [changeset] or [patchset]. +*/ +typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; + +/* +** CAPI3REF: Create A New Session Object +** CONSTRUCTOR: sqlite3_session +** +** Create a new session object attached to database handle db. If successful, +** a pointer to the new object is written to *ppSession and SQLITE_OK is +** returned. If an error occurs, *ppSession is set to NULL and an SQLite +** error code (e.g. SQLITE_NOMEM) is returned. +** +** It is possible to create multiple session objects attached to a single +** database handle. +** +** Session objects created using this function should be deleted using the +** [sqlite3session_delete()] function before the database handle that they +** are attached to is itself closed. If the database handle is closed before +** the session object is deleted, then the results of calling any session +** module function, including [sqlite3session_delete()] on the session object +** are undefined. +** +** Because the session module uses the [sqlite3_preupdate_hook()] API, it +** is not possible for an application to register a pre-update hook on a +** database handle that has one or more session objects attached. Nor is +** it possible to create a session object attached to a database handle for +** which a pre-update hook is already defined. The results of attempting +** either of these things are undefined. +** +** The session object will be used to create changesets for tables in +** database zDb, where zDb is either "main", or "temp", or the name of an +** attached database. It is not an error if database zDb is not attached +** to the database when the session object is created. +*/ +SQLITE_API int sqlite3session_create( + sqlite3 *db, /* Database handle */ + const char *zDb, /* Name of db (e.g. "main") */ + sqlite3_session **ppSession /* OUT: New session object */ +); + +/* +** CAPI3REF: Delete A Session Object +** DESTRUCTOR: sqlite3_session +** +** Delete a session object previously allocated using +** [sqlite3session_create()]. Once a session object has been deleted, the +** results of attempting to use pSession with any other session module +** function are undefined. +** +** Session objects must be deleted before the database handle to which they +** are attached is closed. Refer to the documentation for +** [sqlite3session_create()] for details. +*/ +SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); + +/* +** CAPI3REF: Configure a Session Object +** METHOD: sqlite3_session +** +** This method is used to configure a session object after it has been +** created. At present the only valid values for the second parameter are +** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID]. +** +*/ +SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg); + +/* +** CAPI3REF: Options for sqlite3session_object_config +** +** The following values may passed as the the 2nd parameter to +** sqlite3session_object_config(). +** +**
SQLITE_SESSION_OBJCONFIG_SIZE
+** This option is used to set, clear or query the flag that enables +** the [sqlite3session_changeset_size()] API. Because it imposes some +** computational overhead, this API is disabled by default. Argument +** pArg must point to a value of type (int). If the value is initially +** 0, then the sqlite3session_changeset_size() API is disabled. If it +** is greater than 0, then the same API is enabled. Or, if the initial +** value is less than zero, no change is made. In all cases the (int) +** variable is set to 1 if the sqlite3session_changeset_size() API is +** enabled following the current call, or 0 otherwise. +** +** It is an error (SQLITE_MISUSE) to attempt to modify this setting after +** the first table has been attached to the session object. +** +**
SQLITE_SESSION_OBJCONFIG_ROWID
+** This option is used to set, clear or query the flag that enables +** collection of data for tables with no explicit PRIMARY KEY. +** +** Normally, tables with no explicit PRIMARY KEY are simply ignored +** by the sessions module. However, if this flag is set, it behaves +** as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted +** as their leftmost columns. +** +** It is an error (SQLITE_MISUSE) to attempt to modify this setting after +** the first table has been attached to the session object. +*/ +#define SQLITE_SESSION_OBJCONFIG_SIZE 1 +#define SQLITE_SESSION_OBJCONFIG_ROWID 2 + +/* +** CAPI3REF: Enable Or Disable A Session Object +** METHOD: sqlite3_session +** +** Enable or disable the recording of changes by a session object. When +** enabled, a session object records changes made to the database. When +** disabled - it does not. A newly created session object is enabled. +** Refer to the documentation for [sqlite3session_changeset()] for further +** details regarding how enabling and disabling a session object affects +** the eventual changesets. +** +** Passing zero to this function disables the session. Passing a value +** greater than zero enables it. Passing a value less than zero is a +** no-op, and may be used to query the current state of the session. +** +** The return value indicates the final state of the session object: 0 if +** the session is disabled, or 1 if it is enabled. +*/ +SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); + +/* +** CAPI3REF: Set Or Clear the Indirect Change Flag +** METHOD: sqlite3_session +** +** Each change recorded by a session object is marked as either direct or +** indirect. A change is marked as indirect if either: +** +**
    +**
  • The session object "indirect" flag is set when the change is +** made, or +**
  • The change is made by an SQL trigger or foreign key action +** instead of directly as a result of a users SQL statement. +**
+** +** If a single row is affected by more than one operation within a session, +** then the change is considered indirect if all operations meet the criteria +** for an indirect change above, or direct otherwise. +** +** This function is used to set, clear or query the session object indirect +** flag. If the second argument passed to this function is zero, then the +** indirect flag is cleared. If it is greater than zero, the indirect flag +** is set. Passing a value less than zero does not modify the current value +** of the indirect flag, and may be used to query the current state of the +** indirect flag for the specified session object. +** +** The return value indicates the final state of the indirect flag: 0 if +** it is clear, or 1 if it is set. +*/ +SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); + +/* +** CAPI3REF: Attach A Table To A Session Object +** METHOD: sqlite3_session +** +** If argument zTab is not NULL, then it is the name of a table to attach +** to the session object passed as the first argument. All subsequent changes +** made to the table while the session object is enabled will be recorded. See +** documentation for [sqlite3session_changeset()] for further details. +** +** Or, if argument zTab is NULL, then changes are recorded for all tables +** in the database. If additional tables are added to the database (by +** executing "CREATE TABLE" statements) after this call is made, changes for +** the new tables are also recorded. +** +** Changes can only be recorded for tables that have a PRIMARY KEY explicitly +** defined as part of their CREATE TABLE statement. It does not matter if the +** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY +** KEY may consist of a single column, or may be a composite key. +** +** It is not an error if the named table does not exist in the database. Nor +** is it an error if the named table does not have a PRIMARY KEY. However, +** no changes will be recorded in either of these scenarios. +** +** Changes are not recorded for individual rows that have NULL values stored +** in one or more of their PRIMARY KEY columns. +** +** SQLITE_OK is returned if the call completes without error. Or, if an error +** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. +** +**

Special sqlite_stat1 Handling

+** +** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to +** some of the rules above. In SQLite, the schema of sqlite_stat1 is: +** 
+**        CREATE TABLE sqlite_stat1(tbl,idx,stat)
+**
+** +** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are +** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes +** are recorded for rows for which (idx IS NULL) is true. However, for such +** rows a zero-length blob (SQL value X'') is stored in the changeset or +** patchset instead of a NULL value. This allows such changesets to be +** manipulated by legacy implementations of sqlite3changeset_invert(), +** concat() and similar. +** +** The sqlite3changeset_apply() function automatically converts the +** zero-length blob back to a NULL value when updating the sqlite_stat1 +** table. However, if the application calls sqlite3changeset_new(), +** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset +** iterator directly (including on a changeset iterator passed to a +** conflict-handler callback) then the X'' value is returned. The application +** must translate X'' to NULL itself if required. +** +** Legacy (older than 3.22.0) versions of the sessions module cannot capture +** changes made to the sqlite_stat1 table. Legacy versions of the +** sqlite3changeset_apply() function silently ignore any modifications to the +** sqlite_stat1 table that are part of a changeset or patchset. +*/ +SQLITE_API int sqlite3session_attach( + sqlite3_session *pSession, /* Session object */ + const char *zTab /* Table name */ +); + +/* +** CAPI3REF: Set a table filter on a Session Object. +** METHOD: sqlite3_session +** +** The second argument (xFilter) is the "filter callback". For changes to rows +** in tables that are not attached to the Session object, the filter is called +** to determine whether changes to the table's rows should be tracked or not. +** If xFilter returns 0, changes are not tracked. Note that once a table is +** attached, xFilter will not be called again. +*/ +SQLITE_API void sqlite3session_table_filter( + sqlite3_session *pSession, /* Session object */ + int(*xFilter)( + void *pCtx, /* Copy of third arg to _filter_table() */ + const char *zTab /* Table name */ + ), + void *pCtx /* First argument passed to xFilter */ +); + +/* +** CAPI3REF: Generate A Changeset From A Session Object +** METHOD: sqlite3_session +** +** Obtain a changeset containing changes to the tables attached to the +** session object passed as the first argument. If successful, +** set *ppChangeset to point to a buffer containing the changeset +** and *pnChangeset to the size of the changeset in bytes before returning +** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to +** zero and return an SQLite error code. +** +** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, +** each representing a change to a single row of an attached table. An INSERT +** change contains the values of each field of a new database row. A DELETE +** contains the original values of each field of a deleted database row. An +** UPDATE change contains the original values of each field of an updated +** database row along with the updated values for each updated non-primary-key +** column. It is not possible for an UPDATE change to represent a change that +** modifies the values of primary key columns. If such a change is made, it +** is represented in a changeset as a DELETE followed by an INSERT. +** +** Changes are not recorded for rows that have NULL values stored in one or +** more of their PRIMARY KEY columns. If such a row is inserted or deleted, +** no corresponding change is present in the changesets returned by this +** function. If an existing row with one or more NULL values stored in +** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, +** only an INSERT is appears in the changeset. Similarly, if an existing row +** with non-NULL PRIMARY KEY values is updated so that one or more of its +** PRIMARY KEY columns are set to NULL, the resulting changeset contains a +** DELETE change only. +** +** The contents of a changeset may be traversed using an iterator created +** using the [sqlite3changeset_start()] API. A changeset may be applied to +** a database with a compatible schema using the [sqlite3changeset_apply()] +** API. +** +** Within a changeset generated by this function, all changes related to a +** single table are grouped together. In other words, when iterating through +** a changeset or when applying a changeset to a database, all changes related +** to a single table are processed before moving on to the next table. Tables +** are sorted in the same order in which they were attached (or auto-attached) +** to the sqlite3_session object. The order in which the changes related to +** a single table are stored is undefined. +** +** Following a successful call to this function, it is the responsibility of +** the caller to eventually free the buffer that *ppChangeset points to using +** [sqlite3_free()]. +** +**

Changeset Generation

+** +** Once a table has been attached to a session object, the session object +** records the primary key values of all new rows inserted into the table. +** It also records the original primary key and other column values of any +** deleted or updated rows. For each unique primary key value, data is only +** recorded once - the first time a row with said primary key is inserted, +** updated or deleted in the lifetime of the session. +** +** There is one exception to the previous paragraph: when a row is inserted, +** updated or deleted, if one or more of its primary key columns contain a +** NULL value, no record of the change is made. +** +** The session object therefore accumulates two types of records - those +** that consist of primary key values only (created when the user inserts +** a new record) and those that consist of the primary key values and the +** original values of other table columns (created when the users deletes +** or updates a record). +** +** When this function is called, the requested changeset is created using +** both the accumulated records and the current contents of the database +** file. Specifically: +** +**
    +**
  • For each record generated by an insert, the database is queried +** for a row with a matching primary key. If one is found, an INSERT +** change is added to the changeset. If no such row is found, no change +** is added to the changeset. +** +**
  • For each record generated by an update or delete, the database is +** queried for a row with a matching primary key. If such a row is +** found and one or more of the non-primary key fields have been +** modified from their original values, an UPDATE change is added to +** the changeset. Or, if no such row is found in the table, a DELETE +** change is added to the changeset. If there is a row with a matching +** primary key in the database, but all fields contain their original +** values, no change is added to the changeset. +**
+** +** This means, amongst other things, that if a row is inserted and then later +** deleted while a session object is active, neither the insert nor the delete +** will be present in the changeset. Or if a row is deleted and then later a +** row with the same primary key values inserted while a session object is +** active, the resulting changeset will contain an UPDATE change instead of +** a DELETE and an INSERT. +** +** When a session object is disabled (see the [sqlite3session_enable()] API), +** it does not accumulate records when rows are inserted, updated or deleted. +** This may appear to have some counter-intuitive effects if a single row +** is written to more than once during a session. For example, if a row +** is inserted while a session object is enabled, then later deleted while +** the same session object is disabled, no INSERT record will appear in the +** changeset, even though the delete took place while the session was disabled. +** Or, if one field of a row is updated while a session is disabled, and +** another field of the same row is updated while the session is enabled, the +** resulting changeset will contain an UPDATE change that updates both fields. +*/ +SQLITE_API int sqlite3session_changeset( + sqlite3_session *pSession, /* Session object */ + int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ + void **ppChangeset /* OUT: Buffer containing changeset */ +); + +/* +** CAPI3REF: Return An Upper-limit For The Size Of The Changeset +** METHOD: sqlite3_session +** +** By default, this function always returns 0. For it to return +** a useful result, the sqlite3_session object must have been configured +** to enable this API using sqlite3session_object_config() with the +** SQLITE_SESSION_OBJCONFIG_SIZE verb. +** +** When enabled, this function returns an upper limit, in bytes, for the size +** of the changeset that might be produced if sqlite3session_changeset() were +** called. The final changeset size might be equal to or smaller than the +** size in bytes returned by this function. +*/ +SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession); + +/* +** CAPI3REF: Load The Difference Between Tables Into A Session +** METHOD: sqlite3_session +** +** If it is not already attached to the session object passed as the first +** argument, this function attaches table zTbl in the same manner as the +** [sqlite3session_attach()] function. If zTbl does not exist, or if it +** does not have a primary key, this function is a no-op (but does not return +** an error). +** +** Argument zFromDb must be the name of a database ("main", "temp" etc.) +** attached to the same database handle as the session object that contains +** a table compatible with the table attached to the session by this function. +** A table is considered compatible if it: +** +**
    +**
  • Has the same name, +**
  • Has the same set of columns declared in the same order, and +**
  • Has the same PRIMARY KEY definition. +**
+** +** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables +** are compatible but do not have any PRIMARY KEY columns, it is not an error +** but no changes are added to the session object. As with other session +** APIs, tables without PRIMARY KEYs are simply ignored. +** +** This function adds a set of changes to the session object that could be +** used to update the table in database zFrom (call this the "from-table") +** so that its content is the same as the table attached to the session +** object (call this the "to-table"). Specifically: +** +**
    +**
  • For each row (primary key) that exists in the to-table but not in +** the from-table, an INSERT record is added to the session object. +** +**
  • For each row (primary key) that exists in the to-table but not in +** the from-table, a DELETE record is added to the session object. +** +**
  • For each row (primary key) that exists in both tables, but features +** different non-PK values in each, an UPDATE record is added to the +** session. +**
+** +** To clarify, if this function is called and then a changeset constructed +** using [sqlite3session_changeset()], then after applying that changeset to +** database zFrom the contents of the two compatible tables would be +** identical. +** +** It an error if database zFrom does not exist or does not contain the +** required compatible table. +** +** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite +** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg +** may be set to point to a buffer containing an English language error +** message. It is the responsibility of the caller to free this buffer using +** sqlite3_free(). +*/ +SQLITE_API int sqlite3session_diff( + sqlite3_session *pSession, + const char *zFromDb, + const char *zTbl, + char **pzErrMsg +); + + +/* +** CAPI3REF: Generate A Patchset From A Session Object +** METHOD: sqlite3_session +** +** The differences between a patchset and a changeset are that: +** +**
    +**
  • DELETE records consist of the primary key fields only. The +** original values of other fields are omitted. +**
  • The original values of any modified fields are omitted from +** UPDATE records. +**
+** +** A patchset blob may be used with up to date versions of all +** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), +** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, +** attempting to use a patchset blob with old versions of the +** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. +** +** Because the non-primary key "old.*" fields are omitted, no +** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset +** is passed to the sqlite3changeset_apply() API. Other conflict types work +** in the same way as for changesets. +** +** Changes within a patchset are ordered in the same way as for changesets +** generated by the sqlite3session_changeset() function (i.e. all changes for +** a single table are grouped together, tables appear in the order in which +** they were attached to the session object). +*/ +SQLITE_API int sqlite3session_patchset( + sqlite3_session *pSession, /* Session object */ + int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ + void **ppPatchset /* OUT: Buffer containing patchset */ +); + +/* +** CAPI3REF: Test if a changeset has recorded any changes. +** +** Return non-zero if no changes to attached tables have been recorded by +** the session object passed as the first argument. Otherwise, if one or +** more changes have been recorded, return zero. +** +** Even if this function returns zero, it is possible that calling +** [sqlite3session_changeset()] on the session handle may still return a +** changeset that contains no changes. This can happen when a row in +** an attached table is modified and then later on the original values +** are restored. However, if this function returns non-zero, then it is +** guaranteed that a call to sqlite3session_changeset() will return a +** changeset containing zero changes. +*/ +SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); + +/* +** CAPI3REF: Query for the amount of heap memory used by a session object. +** +** This API returns the total amount of heap memory in bytes currently +** used by the session object passed as the only argument. +*/ +SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession); + +/* +** CAPI3REF: Create An Iterator To Traverse A Changeset +** CONSTRUCTOR: sqlite3_changeset_iter +** +** Create an iterator used to iterate through the contents of a changeset. +** If successful, *pp is set to point to the iterator handle and SQLITE_OK +** is returned. Otherwise, if an error occurs, *pp is set to zero and an +** SQLite error code is returned. +** +** The following functions can be used to advance and query a changeset +** iterator created by this function: +** +**
    +**
  • [sqlite3changeset_next()] +**
  • [sqlite3changeset_op()] +**
  • [sqlite3changeset_new()] +**
  • [sqlite3changeset_old()] +**
+** +** It is the responsibility of the caller to eventually destroy the iterator +** by passing it to [sqlite3changeset_finalize()]. The buffer containing the +** changeset (pChangeset) must remain valid until after the iterator is +** destroyed. +** +** Assuming the changeset blob was created by one of the +** [sqlite3session_changeset()], [sqlite3changeset_concat()] or +** [sqlite3changeset_invert()] functions, all changes within the changeset +** that apply to a single table are grouped together. This means that when +** an application iterates through a changeset using an iterator created by +** this function, all changes that relate to a single table are visited +** consecutively. There is no chance that the iterator will visit a change +** the applies to table X, then one for table Y, and then later on visit +** another change for table X. +** +** The behavior of sqlite3changeset_start_v2() and its streaming equivalent +** may be modified by passing a combination of +** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. +** +** Note that the sqlite3changeset_start_v2() API is still experimental +** and therefore subject to change. +*/ +SQLITE_API int sqlite3changeset_start( + sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ + int nChangeset, /* Size of changeset blob in bytes */ + void *pChangeset /* Pointer to blob containing changeset */ +); +SQLITE_API int sqlite3changeset_start_v2( + sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ + int nChangeset, /* Size of changeset blob in bytes */ + void *pChangeset, /* Pointer to blob containing changeset */ + int flags /* SESSION_CHANGESETSTART_* flags */ +); + +/* +** CAPI3REF: Flags for sqlite3changeset_start_v2 +** +** The following flags may passed via the 4th parameter to +** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: +** +**
SQLITE_CHANGESETAPPLY_INVERT
+** Invert the changeset while iterating through it. This is equivalent to +** inverting a changeset using sqlite3changeset_invert() before applying it. +** It is an error to specify this flag with a patchset. +*/ +#define SQLITE_CHANGESETSTART_INVERT 0x0002 + + +/* +** CAPI3REF: Advance A Changeset Iterator +** METHOD: sqlite3_changeset_iter +** +** This function may only be used with iterators created by the function +** [sqlite3changeset_start()]. If it is called on an iterator passed to +** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE +** is returned and the call has no effect. +** +** Immediately after an iterator is created by sqlite3changeset_start(), it +** does not point to any change in the changeset. Assuming the changeset +** is not empty, the first call to this function advances the iterator to +** point to the first change in the changeset. Each subsequent call advances +** the iterator to point to the next change in the changeset (if any). If +** no error occurs and the iterator points to a valid change after a call +** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. +** Otherwise, if all changes in the changeset have already been visited, +** SQLITE_DONE is returned. +** +** If an error occurs, an SQLite error code is returned. Possible error +** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or +** SQLITE_NOMEM. +*/ +SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); + +/* +** CAPI3REF: Obtain The Current Operation From A Changeset Iterator +** METHOD: sqlite3_changeset_iter +** +** The pIter argument passed to this function may either be an iterator +** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator +** created by [sqlite3changeset_start()]. In the latter case, the most recent +** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this +** is not the case, this function returns [SQLITE_MISUSE]. +** +** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three +** outputs are set through these pointers: +** +** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], +** depending on the type of change that the iterator currently points to; +** +** *pnCol is set to the number of columns in the table affected by the change; and +** +** *pzTab is set to point to a nul-terminated utf-8 encoded string containing +** the name of the table affected by the current change. The buffer remains +** valid until either sqlite3changeset_next() is called on the iterator +** or until the conflict-handler function returns. +** +** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change +** is an indirect change, or false (0) otherwise. See the documentation for +** [sqlite3session_indirect()] for a description of direct and indirect +** changes. +** +** If no error occurs, SQLITE_OK is returned. If an error does occur, an +** SQLite error code is returned. The values of the output variables may not +** be trusted in this case. +*/ +SQLITE_API int sqlite3changeset_op( + sqlite3_changeset_iter *pIter, /* Iterator object */ + const char **pzTab, /* OUT: Pointer to table name */ + int *pnCol, /* OUT: Number of columns in table */ + int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ + int *pbIndirect /* OUT: True for an 'indirect' change */ +); + +/* +** CAPI3REF: Obtain The Primary Key Definition Of A Table +** METHOD: sqlite3_changeset_iter +** +** For each modified table, a changeset includes the following: +** +**
    +**
  • The number of columns in the table, and +**
  • Which of those columns make up the tables PRIMARY KEY. +**
+** +** This function is used to find which columns comprise the PRIMARY KEY of +** the table modified by the change that iterator pIter currently points to. +** If successful, *pabPK is set to point to an array of nCol entries, where +** nCol is the number of columns in the table. Elements of *pabPK are set to +** 0x01 if the corresponding column is part of the tables primary key, or +** 0x00 if it is not. +** +** If argument pnCol is not NULL, then *pnCol is set to the number of columns +** in the table. +** +** If this function is called when the iterator does not point to a valid +** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, +** SQLITE_OK is returned and the output variables populated as described +** above. +*/ +SQLITE_API int sqlite3changeset_pk( + sqlite3_changeset_iter *pIter, /* Iterator object */ + unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ + int *pnCol /* OUT: Number of entries in output array */ +); + +/* +** CAPI3REF: Obtain old.* Values From A Changeset Iterator +** METHOD: sqlite3_changeset_iter +** +** The pIter argument passed to this function may either be an iterator +** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator +** created by [sqlite3changeset_start()]. In the latter case, the most recent +** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. +** Furthermore, it may only be called if the type of change that the iterator +** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, +** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. +** +** Argument iVal must be greater than or equal to 0, and less than the number +** of columns in the table affected by the current change. Otherwise, +** [SQLITE_RANGE] is returned and *ppValue is set to NULL. +** +** If successful, this function sets *ppValue to point to a protected +** sqlite3_value object containing the iVal'th value from the vector of +** original row values stored as part of the UPDATE or DELETE change and +** returns SQLITE_OK. The name of the function comes from the fact that this +** is similar to the "old.*" columns available to update or delete triggers. +** +** If some other error occurs (e.g. an OOM condition), an SQLite error code +** is returned and *ppValue is set to NULL. +*/ +SQLITE_API int sqlite3changeset_old( + sqlite3_changeset_iter *pIter, /* Changeset iterator */ + int iVal, /* Column number */ + sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ +); + +/* +** CAPI3REF: Obtain new.* Values From A Changeset Iterator +** METHOD: sqlite3_changeset_iter +** +** The pIter argument passed to this function may either be an iterator +** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator +** created by [sqlite3changeset_start()]. In the latter case, the most recent +** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. +** Furthermore, it may only be called if the type of change that the iterator +** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, +** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. +** +** Argument iVal must be greater than or equal to 0, and less than the number +** of columns in the table affected by the current change. Otherwise, +** [SQLITE_RANGE] is returned and *ppValue is set to NULL. +** +** If successful, this function sets *ppValue to point to a protected +** sqlite3_value object containing the iVal'th value from the vector of +** new row values stored as part of the UPDATE or INSERT change and +** returns SQLITE_OK. If the change is an UPDATE and does not include +** a new value for the requested column, *ppValue is set to NULL and +** SQLITE_OK returned. The name of the function comes from the fact that +** this is similar to the "new.*" columns available to update or delete +** triggers. +** +** If some other error occurs (e.g. an OOM condition), an SQLite error code +** is returned and *ppValue is set to NULL. +*/ +SQLITE_API int sqlite3changeset_new( + sqlite3_changeset_iter *pIter, /* Changeset iterator */ + int iVal, /* Column number */ + sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ +); + +/* +** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator +** METHOD: sqlite3_changeset_iter +** +** This function should only be used with iterator objects passed to a +** conflict-handler callback by [sqlite3changeset_apply()] with either +** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function +** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue +** is set to NULL. +** +** Argument iVal must be greater than or equal to 0, and less than the number +** of columns in the table affected by the current change. Otherwise, +** [SQLITE_RANGE] is returned and *ppValue is set to NULL. +** +** If successful, this function sets *ppValue to point to a protected +** sqlite3_value object containing the iVal'th value from the +** "conflicting row" associated with the current conflict-handler callback +** and returns SQLITE_OK. +** +** If some other error occurs (e.g. an OOM condition), an SQLite error code +** is returned and *ppValue is set to NULL. +*/ +SQLITE_API int sqlite3changeset_conflict( + sqlite3_changeset_iter *pIter, /* Changeset iterator */ + int iVal, /* Column number */ + sqlite3_value **ppValue /* OUT: Value from conflicting row */ +); + +/* +** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations +** METHOD: sqlite3_changeset_iter +** +** This function may only be called with an iterator passed to an +** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case +** it sets the output variable to the total number of known foreign key +** violations in the destination database and returns SQLITE_OK. +** +** In all other cases this function returns SQLITE_MISUSE. +*/ +SQLITE_API int sqlite3changeset_fk_conflicts( + sqlite3_changeset_iter *pIter, /* Changeset iterator */ + int *pnOut /* OUT: Number of FK violations */ +); + + +/* +** CAPI3REF: Finalize A Changeset Iterator +** METHOD: sqlite3_changeset_iter +** +** This function is used to finalize an iterator allocated with +** [sqlite3changeset_start()]. +** +** This function should only be called on iterators created using the +** [sqlite3changeset_start()] function. If an application calls this +** function with an iterator passed to a conflict-handler by +** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the +** call has no effect. +** +** If an error was encountered within a call to an sqlite3changeset_xxx() +** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an +** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding +** to that error is returned by this function. Otherwise, SQLITE_OK is +** returned. This is to allow the following pattern (pseudo-code): +** +** 
+**   sqlite3changeset_start();
+**   while( SQLITE_ROW==sqlite3changeset_next() ){
+**     // Do something with change.
+**   }
+**   rc = sqlite3changeset_finalize();
+**   if( rc!=SQLITE_OK ){
+**     // An error has occurred
+**   }
+**
+*/ +SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); + +/* +** CAPI3REF: Invert A Changeset +** +** This function is used to "invert" a changeset object. Applying an inverted +** changeset to a database reverses the effects of applying the uninverted +** changeset. Specifically: +** +**
    +**
  • Each DELETE change is changed to an INSERT, and +**
  • Each INSERT change is changed to a DELETE, and +**
  • For each UPDATE change, the old.* and new.* values are exchanged. +**
+** +** This function does not change the order in which changes appear within +** the changeset. It merely reverses the sense of each individual change. +** +** If successful, a pointer to a buffer containing the inverted changeset +** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and +** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are +** zeroed and an SQLite error code returned. +** +** It is the responsibility of the caller to eventually call sqlite3_free() +** on the *ppOut pointer to free the buffer allocation following a successful +** call to this function. +** +** WARNING/TODO: This function currently assumes that the input is a valid +** changeset. If it is not, the results are undefined. +*/ +SQLITE_API int sqlite3changeset_invert( + int nIn, const void *pIn, /* Input changeset */ + int *pnOut, void **ppOut /* OUT: Inverse of input */ +); + +/* +** CAPI3REF: Concatenate Two Changeset Objects +** +** This function is used to concatenate two changesets, A and B, into a +** single changeset. The result is a changeset equivalent to applying +** changeset A followed by changeset B. +** +** This function combines the two input changesets using an +** sqlite3_changegroup object. Calling it produces similar results as the +** following code fragment: +** +** 
+**   sqlite3_changegroup *pGrp;
+**   rc = sqlite3_changegroup_new(&pGrp);
+**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
+**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
+**   if( rc==SQLITE_OK ){
+**     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
+**   }else{
+**     *ppOut = 0;
+**     *pnOut = 0;
+**   }
+**
+** +** Refer to the sqlite3_changegroup documentation below for details. +*/ +SQLITE_API int sqlite3changeset_concat( + int nA, /* Number of bytes in buffer pA */ + void *pA, /* Pointer to buffer containing changeset A */ + int nB, /* Number of bytes in buffer pB */ + void *pB, /* Pointer to buffer containing changeset B */ + int *pnOut, /* OUT: Number of bytes in output changeset */ + void **ppOut /* OUT: Buffer containing output changeset */ +); + + +/* +** CAPI3REF: Upgrade the Schema of a Changeset/Patchset +*/ +SQLITE_API int sqlite3changeset_upgrade( + sqlite3 *db, + const char *zDb, + int nIn, const void *pIn, /* Input changeset */ + int *pnOut, void **ppOut /* OUT: Inverse of input */ +); + + + +/* +** CAPI3REF: Changegroup Handle +** +** A changegroup is an object used to combine two or more +** [changesets] or [patchsets] +*/ +typedef struct sqlite3_changegroup sqlite3_changegroup; + +/* +** CAPI3REF: Create A New Changegroup Object +** CONSTRUCTOR: sqlite3_changegroup +** +** An sqlite3_changegroup object is used to combine two or more changesets +** (or patchsets) into a single changeset (or patchset). A single changegroup +** object may combine changesets or patchsets, but not both. The output is +** always in the same format as the input. +** +** If successful, this function returns SQLITE_OK and populates (*pp) with +** a pointer to a new sqlite3_changegroup object before returning. The caller +** should eventually free the returned object using a call to +** sqlite3changegroup_delete(). If an error occurs, an SQLite error code +** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. +** +** The usual usage pattern for an sqlite3_changegroup object is as follows: +** +**
    +**
  • It is created using a call to sqlite3changegroup_new(). +** +**
  • Zero or more changesets (or patchsets) are added to the object +** by calling sqlite3changegroup_add(). +** +**
  • The result of combining all input changesets together is obtained +** by the application via a call to sqlite3changegroup_output(). +** +**
  • The object is deleted using a call to sqlite3changegroup_delete(). +**
+** +** Any number of calls to add() and output() may be made between the calls to +** new() and delete(), and in any order. +** +** As well as the regular sqlite3changegroup_add() and +** sqlite3changegroup_output() functions, also available are the streaming +** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). +*/ +SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); + +/* +** CAPI3REF: Add a Schema to a Changegroup +** METHOD: sqlite3_changegroup_schema +** +** This method may be used to optionally enforce the rule that the changesets +** added to the changegroup handle must match the schema of database zDb +** ("main", "temp", or the name of an attached database). If +** sqlite3changegroup_add() is called to add a changeset that is not compatible +** with the configured schema, SQLITE_SCHEMA is returned and the changegroup +** object is left in an undefined state. +** +** A changeset schema is considered compatible with the database schema in +** the same way as for sqlite3changeset_apply(). Specifically, for each +** table in the changeset, there exists a database table with: +** +**
    +**
  • The name identified by the changeset, and +**
  • at least as many columns as recorded in the changeset, and +**
  • the primary key columns in the same position as recorded in +** the changeset. +**
+** +** The output of the changegroup object always has the same schema as the +** database nominated using this function. In cases where changesets passed +** to sqlite3changegroup_add() have fewer columns than the corresponding table +** in the database schema, these are filled in using the default column +** values from the database schema. This makes it possible to combined +** changesets that have different numbers of columns for a single table +** within a changegroup, provided that they are otherwise compatible. +*/ +SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb); + +/* +** CAPI3REF: Add A Changeset To A Changegroup +** METHOD: sqlite3_changegroup +** +** Add all changes within the changeset (or patchset) in buffer pData (size +** nData bytes) to the changegroup. +** +** If the buffer contains a patchset, then all prior calls to this function +** on the same changegroup object must also have specified patchsets. Or, if +** the buffer contains a changeset, so must have the earlier calls to this +** function. Otherwise, SQLITE_ERROR is returned and no changes are added +** to the changegroup. +** +** Rows within the changeset and changegroup are identified by the values in +** their PRIMARY KEY columns. A change in the changeset is considered to +** apply to the same row as a change already present in the changegroup if +** the two rows have the same primary key. +** +** Changes to rows that do not already appear in the changegroup are +** simply copied into it. Or, if both the new changeset and the changegroup +** contain changes that apply to a single row, the final contents of the +** changegroup depends on the type of each change, as follows: +** +** +** +** +**
Existing Change New Change Output Change +**
INSERT INSERT +** The new change is ignored. This case does not occur if the new +** changeset was recorded immediately after the changesets already +** added to the changegroup. +**
INSERT UPDATE +** The INSERT change remains in the changegroup. The values in the +** INSERT change are modified as if the row was inserted by the +** existing change and then updated according to the new change. +**
INSERT DELETE +** The existing INSERT is removed from the changegroup. The DELETE is +** not added. +**
UPDATE INSERT +** The new change is ignored. This case does not occur if the new +** changeset was recorded immediately after the changesets already +** added to the changegroup. +**
UPDATE UPDATE +** The existing UPDATE remains within the changegroup. It is amended +** so that the accompanying values are as if the row was updated once +** by the existing change and then again by the new change. +**
UPDATE DELETE +** The existing UPDATE is replaced by the new DELETE within the +** changegroup. +**
DELETE INSERT +** If one or more of the column values in the row inserted by the +** new change differ from those in the row deleted by the existing +** change, the existing DELETE is replaced by an UPDATE within the +** changegroup. Otherwise, if the inserted row is exactly the same +** as the deleted row, the existing DELETE is simply discarded. +**
DELETE UPDATE +** The new change is ignored. This case does not occur if the new +** changeset was recorded immediately after the changesets already +** added to the changegroup. +**
DELETE DELETE +** The new change is ignored. This case does not occur if the new +** changeset was recorded immediately after the changesets already +** added to the changegroup. +**
+** +** If the new changeset contains changes to a table that is already present +** in the changegroup, then the number of columns and the position of the +** primary key columns for the table must be consistent. If this is not the +** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup +** object has been configured with a database schema using the +** sqlite3changegroup_schema() API, then it is possible to combine changesets +** with different numbers of columns for a single table, provided that +** they are otherwise compatible. +** +** If the input changeset appears to be corrupt and the corruption is +** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition +** occurs during processing, this function returns SQLITE_NOMEM. +** +** In all cases, if an error occurs the state of the final contents of the +** changegroup is undefined. If no error occurs, SQLITE_OK is returned. +*/ +SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); + +/* +** CAPI3REF: Add A Single Change To A Changegroup +** METHOD: sqlite3_changegroup +** +** This function adds the single change currently indicated by the iterator +** passed as the second argument to the changegroup object. The rules for +** adding the change are just as described for [sqlite3changegroup_add()]. +** +** If the change is successfully added to the changegroup, SQLITE_OK is +** returned. Otherwise, an SQLite error code is returned. +** +** The iterator must point to a valid entry when this function is called. +** If it does not, SQLITE_ERROR is returned and no change is added to the +** changegroup. Additionally, the iterator must not have been opened with +** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also +** returned. +*/ +SQLITE_API int sqlite3changegroup_add_change( + sqlite3_changegroup*, + sqlite3_changeset_iter* +); + + + +/* +** CAPI3REF: Obtain A Composite Changeset From A Changegroup +** METHOD: sqlite3_changegroup +** +** Obtain a buffer containing a changeset (or patchset) representing the +** current contents of the changegroup. If the inputs to the changegroup +** were themselves changesets, the output is a changeset. Or, if the +** inputs were patchsets, the output is also a patchset. +** +** As with the output of the sqlite3session_changeset() and +** sqlite3session_patchset() functions, all changes related to a single +** table are grouped together in the output of this function. Tables appear +** in the same order as for the very first changeset added to the changegroup. +** If the second or subsequent changesets added to the changegroup contain +** changes for tables that do not appear in the first changeset, they are +** appended onto the end of the output changeset, again in the order in +** which they are first encountered. +** +** If an error occurs, an SQLite error code is returned and the output +** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK +** is returned and the output variables are set to the size of and a +** pointer to the output buffer, respectively. In this case it is the +** responsibility of the caller to eventually free the buffer using a +** call to sqlite3_free(). +*/ +SQLITE_API int sqlite3changegroup_output( + sqlite3_changegroup*, + int *pnData, /* OUT: Size of output buffer in bytes */ + void **ppData /* OUT: Pointer to output buffer */ +); + +/* +** CAPI3REF: Delete A Changegroup Object +** DESTRUCTOR: sqlite3_changegroup +*/ +SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); + +/* +** CAPI3REF: Apply A Changeset To A Database +** +** Apply a changeset or patchset to a database. These functions attempt to +** update the "main" database attached to handle db with the changes found in +** the changeset passed via the second and third arguments. +** +** The fourth argument (xFilter) passed to these functions is the "filter +** callback". If it is not NULL, then for each table affected by at least one +** change in the changeset, the filter callback is invoked with +** the table name as the second argument, and a copy of the context pointer +** passed as the sixth argument as the first. If the "filter callback" +** returns zero, then no attempt is made to apply any changes to the table. +** Otherwise, if the return value is non-zero or the xFilter argument to +** is NULL, all changes related to the table are attempted. +** +** For each table that is not excluded by the filter callback, this function +** tests that the target database contains a compatible table. A table is +** considered compatible if all of the following are true: +** +**
    +**
  • The table has the same name as the name recorded in the +** changeset, and +**
  • The table has at least as many columns as recorded in the +** changeset, and +**
  • The table has primary key columns in the same position as +** recorded in the changeset. +**
+** +** If there is no compatible table, it is not an error, but none of the +** changes associated with the table are applied. A warning message is issued +** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most +** one such warning is issued for each table in the changeset. +** +** For each change for which there is a compatible table, an attempt is made +** to modify the table contents according to the UPDATE, INSERT or DELETE +** change. If a change cannot be applied cleanly, the conflict handler +** function passed as the fifth argument to sqlite3changeset_apply() may be +** invoked. A description of exactly when the conflict handler is invoked for +** each type of change is below. +** +** Unlike the xFilter argument, xConflict may not be passed NULL. The results +** of passing anything other than a valid function pointer as the xConflict +** argument are undefined. +** +** Each time the conflict handler function is invoked, it must return one +** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or +** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned +** if the second argument passed to the conflict handler is either +** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler +** returns an illegal value, any changes already made are rolled back and +** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different +** actions are taken by sqlite3changeset_apply() depending on the value +** returned by each invocation of the conflict-handler function. Refer to +** the documentation for the three +** [SQLITE_CHANGESET_OMIT|available return values] for details. +** +**
+**
DELETE Changes
+** For each DELETE change, the function checks if the target database +** contains a row with the same primary key value (or values) as the +** original row values stored in the changeset. If it does, and the values +** stored in all non-primary key columns also match the values stored in +** the changeset the row is deleted from the target database. +** +** If a row with matching primary key values is found, but one or more of +** the non-primary key fields contains a value different from the original +** row value stored in the changeset, the conflict-handler function is +** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the +** database table has more columns than are recorded in the changeset, +** only the values of those non-primary key fields are compared against +** the current database contents - any trailing database table columns +** are ignored. +** +** If no row with matching primary key values is found in the database, +** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] +** passed as the second argument. +** +** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT +** (which can only happen if a foreign key constraint is violated), the +** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] +** passed as the second argument. This includes the case where the DELETE +** operation is attempted because an earlier call to the conflict handler +** function returned [SQLITE_CHANGESET_REPLACE]. +** +**
INSERT Changes
+** For each INSERT change, an attempt is made to insert the new row into +** the database. If the changeset row contains fewer fields than the +** database table, the trailing fields are populated with their default +** values. +** +** If the attempt to insert the row fails because the database already +** contains a row with the same primary key values, the conflict handler +** function is invoked with the second argument set to +** [SQLITE_CHANGESET_CONFLICT]. +** +** If the attempt to insert the row fails because of some other constraint +** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is +** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. +** This includes the case where the INSERT operation is re-attempted because +** an earlier call to the conflict handler function returned +** [SQLITE_CHANGESET_REPLACE]. +** +**
UPDATE Changes
+** For each UPDATE change, the function checks if the target database +** contains a row with the same primary key value (or values) as the +** original row values stored in the changeset. If it does, and the values +** stored in all modified non-primary key columns also match the values +** stored in the changeset the row is updated within the target database. +** +** If a row with matching primary key values is found, but one or more of +** the modified non-primary key fields contains a value different from an +** original row value stored in the changeset, the conflict-handler function +** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since +** UPDATE changes only contain values for non-primary key fields that are +** to be modified, only those fields need to match the original values to +** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. +** +** If no row with matching primary key values is found in the database, +** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] +** passed as the second argument. +** +** If the UPDATE operation is attempted, but SQLite returns +** SQLITE_CONSTRAINT, the conflict-handler function is invoked with +** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. +** This includes the case where the UPDATE operation is attempted after +** an earlier call to the conflict handler function returned +** [SQLITE_CHANGESET_REPLACE]. +**
+** +** It is safe to execute SQL statements, including those that write to the +** table that the callback related to, from within the xConflict callback. +** This can be used to further customize the application's conflict +** resolution strategy. +** +** All changes made by these functions are enclosed in a savepoint transaction. +** If any other error (aside from a constraint failure when attempting to +** write to the target database) occurs, then the savepoint transaction is +** rolled back, restoring the target database to its original state, and an +** SQLite error code returned. +** +** If the output parameters (ppRebase) and (pnRebase) are non-NULL and +** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() +** may set (*ppRebase) to point to a "rebase" that may be used with the +** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) +** is set to the size of the buffer in bytes. It is the responsibility of the +** caller to eventually free any such buffer using sqlite3_free(). The buffer +** is only allocated and populated if one or more conflicts were encountered +** while applying the patchset. See comments surrounding the sqlite3_rebaser +** APIs for further details. +** +** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent +** may be modified by passing a combination of +** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. +** +** Note that the sqlite3changeset_apply_v2() API is still experimental +** and therefore subject to change. +*/ +SQLITE_API int sqlite3changeset_apply( + sqlite3 *db, /* Apply change to "main" db of this handle */ + int nChangeset, /* Size of changeset in bytes */ + void *pChangeset, /* Changeset blob */ + int(*xFilter)( + void *pCtx, /* Copy of sixth arg to _apply() */ + const char *zTab /* Table name */ + ), + int(*xConflict)( + void *pCtx, /* Copy of sixth arg to _apply() */ + int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ + sqlite3_changeset_iter *p /* Handle describing change and conflict */ + ), + void *pCtx /* First argument passed to xConflict */ +); +SQLITE_API int sqlite3changeset_apply_v2( + sqlite3 *db, /* Apply change to "main" db of this handle */ + int nChangeset, /* Size of changeset in bytes */ + void *pChangeset, /* Changeset blob */ + int(*xFilter)( + void *pCtx, /* Copy of sixth arg to _apply() */ + const char *zTab /* Table name */ + ), + int(*xConflict)( + void *pCtx, /* Copy of sixth arg to _apply() */ + int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ + sqlite3_changeset_iter *p /* Handle describing change and conflict */ + ), + void *pCtx, /* First argument passed to xConflict */ + void **ppRebase, int *pnRebase, /* OUT: Rebase data */ + int flags /* SESSION_CHANGESETAPPLY_* flags */ +); + +/* +** CAPI3REF: Flags for sqlite3changeset_apply_v2 +** +** The following flags may passed via the 9th parameter to +** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: +** +**
+**
SQLITE_CHANGESETAPPLY_NOSAVEPOINT
+** Usually, the sessions module encloses all operations performed by +** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The +** SAVEPOINT is committed if the changeset or patchset is successfully +** applied, or rolled back if an error occurs. Specifying this flag +** causes the sessions module to omit this savepoint. In this case, if the +** caller has an open transaction or savepoint when apply_v2() is called, +** it may revert the partially applied changeset by rolling it back. +** +**
SQLITE_CHANGESETAPPLY_INVERT
+** Invert the changeset before applying it. This is equivalent to inverting +** a changeset using sqlite3changeset_invert() before applying it. It is +** an error to specify this flag with a patchset. +** +**
SQLITE_CHANGESETAPPLY_IGNORENOOP
+** Do not invoke the conflict handler callback for any changes that +** would not actually modify the database even if they were applied. +** Specifically, this means that the conflict handler is not invoked +** for: +**
    +**
  • a delete change if the row being deleted cannot be found, +**
  • an update change if the modified fields are already set to +** their new values in the conflicting row, or +**
  • an insert change if all fields of the conflicting row match +** the row being inserted. +**
+** +**
SQLITE_CHANGESETAPPLY_FKNOACTION
+** If this flag it set, then all foreign key constraints in the target +** database behave as if they were declared with "ON UPDATE NO ACTION ON +** DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL +** or SET DEFAULT. +*/ +#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 +#define SQLITE_CHANGESETAPPLY_INVERT 0x0002 +#define SQLITE_CHANGESETAPPLY_IGNORENOOP 0x0004 +#define SQLITE_CHANGESETAPPLY_FKNOACTION 0x0008 + +/* +** CAPI3REF: Constants Passed To The Conflict Handler +** +** Values that may be passed as the second argument to a conflict-handler. +** +**
+**
SQLITE_CHANGESET_DATA
+** The conflict handler is invoked with CHANGESET_DATA as the second argument +** when processing a DELETE or UPDATE change if a row with the required +** PRIMARY KEY fields is present in the database, but one or more other +** (non primary-key) fields modified by the update do not contain the +** expected "before" values. +** +** The conflicting row, in this case, is the database row with the matching +** primary key. +** +**
SQLITE_CHANGESET_NOTFOUND
+** The conflict handler is invoked with CHANGESET_NOTFOUND as the second +** argument when processing a DELETE or UPDATE change if a row with the +** required PRIMARY KEY fields is not present in the database. +** +** There is no conflicting row in this case. The results of invoking the +** sqlite3changeset_conflict() API are undefined. +** +**
SQLITE_CHANGESET_CONFLICT
+** CHANGESET_CONFLICT is passed as the second argument to the conflict +** handler while processing an INSERT change if the operation would result +** in duplicate primary key values. +** +** The conflicting row in this case is the database row with the matching +** primary key. +** +**
SQLITE_CHANGESET_FOREIGN_KEY
+** If foreign key handling is enabled, and applying a changeset leaves the +** database in a state containing foreign key violations, the conflict +** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument +** exactly once before the changeset is committed. If the conflict handler +** returns CHANGESET_OMIT, the changes, including those that caused the +** foreign key constraint violation, are committed. Or, if it returns +** CHANGESET_ABORT, the changeset is rolled back. +** +** No current or conflicting row information is provided. The only function +** it is possible to call on the supplied sqlite3_changeset_iter handle +** is sqlite3changeset_fk_conflicts(). +** +**
SQLITE_CHANGESET_CONSTRAINT
+** If any other constraint violation occurs while applying a change (i.e. +** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is +** invoked with CHANGESET_CONSTRAINT as the second argument. +** +** There is no conflicting row in this case. The results of invoking the +** sqlite3changeset_conflict() API are undefined. +** +**
+*/ +#define SQLITE_CHANGESET_DATA 1 +#define SQLITE_CHANGESET_NOTFOUND 2 +#define SQLITE_CHANGESET_CONFLICT 3 +#define SQLITE_CHANGESET_CONSTRAINT 4 +#define SQLITE_CHANGESET_FOREIGN_KEY 5 + +/* +** CAPI3REF: Constants Returned By The Conflict Handler +** +** A conflict handler callback must return one of the following three values. +** +**
+**
SQLITE_CHANGESET_OMIT
+** If a conflict handler returns this value no special action is taken. The +** change that caused the conflict is not applied. The session module +** continues to the next change in the changeset. +** +**
SQLITE_CHANGESET_REPLACE
+** This value may only be returned if the second argument to the conflict +** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this +** is not the case, any changes applied so far are rolled back and the +** call to sqlite3changeset_apply() returns SQLITE_MISUSE. +** +** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict +** handler, then the conflicting row is either updated or deleted, depending +** on the type of change. +** +** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict +** handler, then the conflicting row is removed from the database and a +** second attempt to apply the change is made. If this second attempt fails, +** the original row is restored to the database before continuing. +** +**
SQLITE_CHANGESET_ABORT
+** If this value is returned, any changes applied so far are rolled back +** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. +**
+*/ +#define SQLITE_CHANGESET_OMIT 0 +#define SQLITE_CHANGESET_REPLACE 1 +#define SQLITE_CHANGESET_ABORT 2 + +/* +** CAPI3REF: Rebasing changesets +** EXPERIMENTAL +** +** Suppose there is a site hosting a database in state S0. And that +** modifications are made that move that database to state S1 and a +** changeset recorded (the "local" changeset). Then, a changeset based +** on S0 is received from another site (the "remote" changeset) and +** applied to the database. The database is then in state +** (S1+"remote"), where the exact state depends on any conflict +** resolution decisions (OMIT or REPLACE) made while applying "remote". +** Rebasing a changeset is to update it to take those conflict +** resolution decisions into account, so that the same conflicts +** do not have to be resolved elsewhere in the network. +** +** For example, if both the local and remote changesets contain an +** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": +** +** local: INSERT INTO t1 VALUES(1, 'v1'); +** remote: INSERT INTO t1 VALUES(1, 'v2'); +** +** and the conflict resolution is REPLACE, then the INSERT change is +** removed from the local changeset (it was overridden). Or, if the +** conflict resolution was "OMIT", then the local changeset is modified +** to instead contain: +** +** UPDATE t1 SET b = 'v2' WHERE a=1; +** +** Changes within the local changeset are rebased as follows: +** +**
+**
Local INSERT
+** This may only conflict with a remote INSERT. If the conflict +** resolution was OMIT, then add an UPDATE change to the rebased +** changeset. Or, if the conflict resolution was REPLACE, add +** nothing to the rebased changeset. +** +**
Local DELETE
+** This may conflict with a remote UPDATE or DELETE. In both cases the +** only possible resolution is OMIT. If the remote operation was a +** DELETE, then add no change to the rebased changeset. If the remote +** operation was an UPDATE, then the old.* fields of change are updated +** to reflect the new.* values in the UPDATE. +** +**
Local UPDATE
+** This may conflict with a remote UPDATE or DELETE. If it conflicts +** with a DELETE, and the conflict resolution was OMIT, then the update +** is changed into an INSERT. Any undefined values in the new.* record +** from the update change are filled in using the old.* values from +** the conflicting DELETE. Or, if the conflict resolution was REPLACE, +** the UPDATE change is simply omitted from the rebased changeset. +** +** If conflict is with a remote UPDATE and the resolution is OMIT, then +** the old.* values are rebased using the new.* values in the remote +** change. Or, if the resolution is REPLACE, then the change is copied +** into the rebased changeset with updates to columns also updated by +** the conflicting remote UPDATE removed. If this means no columns would +** be updated, the change is omitted. +**
+** +** A local change may be rebased against multiple remote changes +** simultaneously. If a single key is modified by multiple remote +** changesets, they are combined as follows before the local changeset +** is rebased: +** +**
    +**
  • If there has been one or more REPLACE resolutions on a +** key, it is rebased according to a REPLACE. +** +**
  • If there have been no REPLACE resolutions on a key, then +** the local changeset is rebased according to the most recent +** of the OMIT resolutions. +**
+** +** Note that conflict resolutions from multiple remote changesets are +** combined on a per-field basis, not per-row. This means that in the +** case of multiple remote UPDATE operations, some fields of a single +** local change may be rebased for REPLACE while others are rebased for +** OMIT. +** +** In order to rebase a local changeset, the remote changeset must first +** be applied to the local database using sqlite3changeset_apply_v2() and +** the buffer of rebase information captured. Then: +** +**
    +**
  1. An sqlite3_rebaser object is created by calling +** sqlite3rebaser_create(). +**
  2. The new object is configured with the rebase buffer obtained from +** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). +** If the local changeset is to be rebased against multiple remote +** changesets, then sqlite3rebaser_configure() should be called +** multiple times, in the same order that the multiple +** sqlite3changeset_apply_v2() calls were made. +**
  3. Each local changeset is rebased by calling sqlite3rebaser_rebase(). +**
  4. The sqlite3_rebaser object is deleted by calling +** sqlite3rebaser_delete(). +**
+*/ +typedef struct sqlite3_rebaser sqlite3_rebaser; + +/* +** CAPI3REF: Create a changeset rebaser object. +** EXPERIMENTAL +** +** Allocate a new changeset rebaser object. If successful, set (*ppNew) to +** point to the new object and return SQLITE_OK. Otherwise, if an error +** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) +** to NULL. +*/ +SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); + +/* +** CAPI3REF: Configure a changeset rebaser object. +** EXPERIMENTAL +** +** Configure the changeset rebaser object to rebase changesets according +** to the conflict resolutions described by buffer pRebase (size nRebase +** bytes), which must have been obtained from a previous call to +** sqlite3changeset_apply_v2(). +*/ +SQLITE_API int sqlite3rebaser_configure( + sqlite3_rebaser*, + int nRebase, const void *pRebase +); + +/* +** CAPI3REF: Rebase a changeset +** EXPERIMENTAL +** +** Argument pIn must point to a buffer containing a changeset nIn bytes +** in size. This function allocates and populates a buffer with a copy +** of the changeset rebased according to the configuration of the +** rebaser object passed as the first argument. If successful, (*ppOut) +** is set to point to the new buffer containing the rebased changeset and +** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the +** responsibility of the caller to eventually free the new buffer using +** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) +** are set to zero and an SQLite error code returned. +*/ +SQLITE_API int sqlite3rebaser_rebase( + sqlite3_rebaser*, + int nIn, const void *pIn, + int *pnOut, void **ppOut +); + +/* +** CAPI3REF: Delete a changeset rebaser object. +** EXPERIMENTAL +** +** Delete the changeset rebaser object and all associated resources. There +** should be one call to this function for each successful invocation +** of sqlite3rebaser_create(). +*/ +SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); + +/* +** CAPI3REF: Streaming Versions of API functions. +** +** The six streaming API xxx_strm() functions serve similar purposes to the +** corresponding non-streaming API functions: +** +** +** +**
Streaming functionNon-streaming equivalent
sqlite3changeset_apply_strm[sqlite3changeset_apply] +**
sqlite3changeset_apply_strm_v2[sqlite3changeset_apply_v2] +**
sqlite3changeset_concat_strm[sqlite3changeset_concat] +**
sqlite3changeset_invert_strm[sqlite3changeset_invert] +**
sqlite3changeset_start_strm[sqlite3changeset_start] +**
sqlite3session_changeset_strm[sqlite3session_changeset] +**
sqlite3session_patchset_strm[sqlite3session_patchset] +**
+** +** Non-streaming functions that accept changesets (or patchsets) as input +** require that the entire changeset be stored in a single buffer in memory. +** Similarly, those that return a changeset or patchset do so by returning +** a pointer to a single large buffer allocated using sqlite3_malloc(). +** Normally this is convenient. However, if an application running in a +** low-memory environment is required to handle very large changesets, the +** large contiguous memory allocations required can become onerous. +** +** In order to avoid this problem, instead of a single large buffer, input +** is passed to a streaming API functions by way of a callback function that +** the sessions module invokes to incrementally request input data as it is +** required. In all cases, a pair of API function parameters such as +** +** 
+**        int nChangeset,
+**        void *pChangeset,
+**
+** +** Is replaced by: +** +** 
+**        int (*xInput)(void *pIn, void *pData, int *pnData),
+**        void *pIn,
+**
+** +** Each time the xInput callback is invoked by the sessions module, the first +** argument passed is a copy of the supplied pIn context pointer. The second +** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no +** error occurs the xInput method should copy up to (*pnData) bytes of data +** into the buffer and set (*pnData) to the actual number of bytes copied +** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) +** should be set to zero to indicate this. Or, if an error occurs, an SQLite +** error code should be returned. In all cases, if an xInput callback returns +** an error, all processing is abandoned and the streaming API function +** returns a copy of the error code to the caller. +** +** In the case of sqlite3changeset_start_strm(), the xInput callback may be +** invoked by the sessions module at any point during the lifetime of the +** iterator. If such an xInput callback returns an error, the iterator enters +** an error state, whereby all subsequent calls to iterator functions +** immediately fail with the same error code as returned by xInput. +** +** Similarly, streaming API functions that return changesets (or patchsets) +** return them in chunks by way of a callback function instead of via a +** pointer to a single large buffer. In this case, a pair of parameters such +** as: +** +** 
+**        int *pnChangeset,
+**        void **ppChangeset,
+**
+** +** Is replaced by: +** +** 
+**        int (*xOutput)(void *pOut, const void *pData, int nData),
+**        void *pOut
+**
+** +** The xOutput callback is invoked zero or more times to return data to +** the application. The first parameter passed to each call is a copy of the +** pOut pointer supplied by the application. The second parameter, pData, +** points to a buffer nData bytes in size containing the chunk of output +** data being returned. If the xOutput callback successfully processes the +** supplied data, it should return SQLITE_OK to indicate success. Otherwise, +** it should return some other SQLite error code. In this case processing +** is immediately abandoned and the streaming API function returns a copy +** of the xOutput error code to the application. +** +** The sessions module never invokes an xOutput callback with the third +** parameter set to a value less than or equal to zero. Other than this, +** no guarantees are made as to the size of the chunks of data returned. +*/ +SQLITE_API int sqlite3changeset_apply_strm( + sqlite3 *db, /* Apply change to "main" db of this handle */ + int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ + void *pIn, /* First arg for xInput */ + int(*xFilter)( + void *pCtx, /* Copy of sixth arg to _apply() */ + const char *zTab /* Table name */ + ), + int(*xConflict)( + void *pCtx, /* Copy of sixth arg to _apply() */ + int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ + sqlite3_changeset_iter *p /* Handle describing change and conflict */ + ), + void *pCtx /* First argument passed to xConflict */ +); +SQLITE_API int sqlite3changeset_apply_v2_strm( + sqlite3 *db, /* Apply change to "main" db of this handle */ + int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ + void *pIn, /* First arg for xInput */ + int(*xFilter)( + void *pCtx, /* Copy of sixth arg to _apply() */ + const char *zTab /* Table name */ + ), + int(*xConflict)( + void *pCtx, /* Copy of sixth arg to _apply() */ + int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ + sqlite3_changeset_iter *p /* Handle describing change and conflict */ + ), + void *pCtx, /* First argument passed to xConflict */ + void **ppRebase, int *pnRebase, + int flags +); +SQLITE_API int sqlite3changeset_concat_strm( + int (*xInputA)(void *pIn, void *pData, int *pnData), + void *pInA, + int (*xInputB)(void *pIn, void *pData, int *pnData), + void *pInB, + int (*xOutput)(void *pOut, const void *pData, int nData), + void *pOut +); +SQLITE_API int sqlite3changeset_invert_strm( + int (*xInput)(void *pIn, void *pData, int *pnData), + void *pIn, + int (*xOutput)(void *pOut, const void *pData, int nData), + void *pOut +); +SQLITE_API int sqlite3changeset_start_strm( + sqlite3_changeset_iter **pp, + int (*xInput)(void *pIn, void *pData, int *pnData), + void *pIn +); +SQLITE_API int sqlite3changeset_start_v2_strm( + sqlite3_changeset_iter **pp, + int (*xInput)(void *pIn, void *pData, int *pnData), + void *pIn, + int flags +); +SQLITE_API int sqlite3session_changeset_strm( + sqlite3_session *pSession, + int (*xOutput)(void *pOut, const void *pData, int nData), + void *pOut +); +SQLITE_API int sqlite3session_patchset_strm( + sqlite3_session *pSession, + int (*xOutput)(void *pOut, const void *pData, int nData), + void *pOut +); +SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, + int (*xInput)(void *pIn, void *pData, int *pnData), + void *pIn +); +SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, + int (*xOutput)(void *pOut, const void *pData, int nData), + void *pOut +); +SQLITE_API int sqlite3rebaser_rebase_strm( + sqlite3_rebaser *pRebaser, + int (*xInput)(void *pIn, void *pData, int *pnData), + void *pIn, + int (*xOutput)(void *pOut, const void *pData, int nData), + void *pOut +); + +/* +** CAPI3REF: Configure global parameters +** +** The sqlite3session_config() interface is used to make global configuration +** changes to the sessions module in order to tune it to the specific needs +** of the application. +** +** The sqlite3session_config() interface is not threadsafe. If it is invoked +** while any other thread is inside any other sessions method then the +** results are undefined. Furthermore, if it is invoked after any sessions +** related objects have been created, the results are also undefined. +** +** The first argument to the sqlite3session_config() function must be one +** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The +** interpretation of the (void*) value passed as the second parameter and +** the effect of calling this function depends on the value of the first +** parameter. +** +**
+**
SQLITE_SESSION_CONFIG_STRMSIZE
+** By default, the sessions module streaming interfaces attempt to input +** and output data in approximately 1 KiB chunks. This operand may be used +** to set and query the value of this configuration setting. The pointer +** passed as the second argument must point to a value of type (int). +** If this value is greater than 0, it is used as the new streaming data +** chunk size for both input and output. Before returning, the (int) value +** pointed to by pArg is set to the final value of the streaming interface +** chunk size. +**
+** +** This function returns SQLITE_OK if successful, or an SQLite error code +** otherwise. +*/ +SQLITE_API int sqlite3session_config(int op, void *pArg); + +/* +** CAPI3REF: Values for sqlite3session_config(). +*/ +#define SQLITE_SESSION_CONFIG_STRMSIZE 1 + +/* +** Make sure we can call this stuff from C++. +*/ +#ifdef __cplusplus +} +#endif + +#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ + +/******** End of sqlite3session.h *********/ +/******** Begin file fts5.h *********/ +/* +** 2014 May 31 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +****************************************************************************** +** +** Interfaces to extend FTS5. Using the interfaces defined in this file, +** FTS5 may be extended with: +** +** * custom tokenizers, and +** * custom auxiliary functions. +*/ + + +#ifndef _FTS5_H +#define _FTS5_H + + +#ifdef __cplusplus +extern "C" { +#endif + +/************************************************************************* +** CUSTOM AUXILIARY FUNCTIONS +** +** Virtual table implementations may overload SQL functions by implementing +** the sqlite3_module.xFindFunction() method. +*/ + +typedef struct Fts5ExtensionApi Fts5ExtensionApi; +typedef struct Fts5Context Fts5Context; +typedef struct Fts5PhraseIter Fts5PhraseIter; + +typedef void (*fts5_extension_function)( + const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ + Fts5Context *pFts, /* First arg to pass to pApi functions */ + sqlite3_context *pCtx, /* Context for returning result/error */ + int nVal, /* Number of values in apVal[] array */ + sqlite3_value **apVal /* Array of trailing arguments */ +); + +struct Fts5PhraseIter { + const unsigned char *a; + const unsigned char *b; +}; + +/* +** EXTENSION API FUNCTIONS +** +** xUserData(pFts): +** Return a copy of the pUserData pointer passed to the xCreateFunction() +** API when the extension function was registered. +** +** xColumnTotalSize(pFts, iCol, pnToken): +** If parameter iCol is less than zero, set output variable *pnToken +** to the total number of tokens in the FTS5 table. Or, if iCol is +** non-negative but less than the number of columns in the table, return +** the total number of tokens in column iCol, considering all rows in +** the FTS5 table. +** +** If parameter iCol is greater than or equal to the number of columns +** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. +** an OOM condition or IO error), an appropriate SQLite error code is +** returned. +** +** xColumnCount(pFts): +** Return the number of columns in the table. +** +** xColumnSize(pFts, iCol, pnToken): +** If parameter iCol is less than zero, set output variable *pnToken +** to the total number of tokens in the current row. Or, if iCol is +** non-negative but less than the number of columns in the table, set +** *pnToken to the number of tokens in column iCol of the current row. +** +** If parameter iCol is greater than or equal to the number of columns +** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. +** an OOM condition or IO error), an appropriate SQLite error code is +** returned. +** +** This function may be quite inefficient if used with an FTS5 table +** created with the "columnsize=0" option. +** +** xColumnText: +** If parameter iCol is less than zero, or greater than or equal to the +** number of columns in the table, SQLITE_RANGE is returned. +** +** Otherwise, this function attempts to retrieve the text of column iCol of +** the current document. If successful, (*pz) is set to point to a buffer +** containing the text in utf-8 encoding, (*pn) is set to the size in bytes +** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, +** if an error occurs, an SQLite error code is returned and the final values +** of (*pz) and (*pn) are undefined. +** +** xPhraseCount: +** Returns the number of phrases in the current query expression. +** +** xPhraseSize: +** If parameter iCol is less than zero, or greater than or equal to the +** number of phrases in the current query, as returned by xPhraseCount, +** 0 is returned. Otherwise, this function returns the number of tokens in +** phrase iPhrase of the query. Phrases are numbered starting from zero. +** +** xInstCount: +** Set *pnInst to the total number of occurrences of all phrases within +** the query within the current row. Return SQLITE_OK if successful, or +** an error code (i.e. SQLITE_NOMEM) if an error occurs. +** +** This API can be quite slow if used with an FTS5 table created with the +** "detail=none" or "detail=column" option. If the FTS5 table is created +** with either "detail=none" or "detail=column" and "content=" option +** (i.e. if it is a contentless table), then this API always returns 0. +** +** xInst: +** Query for the details of phrase match iIdx within the current row. +** Phrase matches are numbered starting from zero, so the iIdx argument +** should be greater than or equal to zero and smaller than the value +** output by xInstCount(). If iIdx is less than zero or greater than +** or equal to the value returned by xInstCount(), SQLITE_RANGE is returned. +** +** Otherwise, output parameter *piPhrase is set to the phrase number, *piCol +** to the column in which it occurs and *piOff the token offset of the +** first token of the phrase. SQLITE_OK is returned if successful, or an +** error code (i.e. SQLITE_NOMEM) if an error occurs. +** +** This API can be quite slow if used with an FTS5 table created with the +** "detail=none" or "detail=column" option. +** +** xRowid: +** Returns the rowid of the current row. +** +** xTokenize: +** Tokenize text using the tokenizer belonging to the FTS5 table. +** +** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): +** This API function is used to query the FTS table for phrase iPhrase +** of the current query. Specifically, a query equivalent to: +** +** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid +** +** with $p set to a phrase equivalent to the phrase iPhrase of the +** current query is executed. Any column filter that applies to +** phrase iPhrase of the current query is included in $p. For each +** row visited, the callback function passed as the fourth argument +** is invoked. The context and API objects passed to the callback +** function may be used to access the properties of each matched row. +** Invoking Api.xUserData() returns a copy of the pointer passed as +** the third argument to pUserData. +** +** If parameter iPhrase is less than zero, or greater than or equal to +** the number of phrases in the query, as returned by xPhraseCount(), +** this function returns SQLITE_RANGE. +** +** If the callback function returns any value other than SQLITE_OK, the +** query is abandoned and the xQueryPhrase function returns immediately. +** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. +** Otherwise, the error code is propagated upwards. +** +** If the query runs to completion without incident, SQLITE_OK is returned. +** Or, if some error occurs before the query completes or is aborted by +** the callback, an SQLite error code is returned. +** +** +** xSetAuxdata(pFts5, pAux, xDelete) +** +** Save the pointer passed as the second argument as the extension function's +** "auxiliary data". The pointer may then be retrieved by the current or any +** future invocation of the same fts5 extension function made as part of +** the same MATCH query using the xGetAuxdata() API. +** +** Each extension function is allocated a single auxiliary data slot for +** each FTS query (MATCH expression). If the extension function is invoked +** more than once for a single FTS query, then all invocations share a +** single auxiliary data context. +** +** If there is already an auxiliary data pointer when this function is +** invoked, then it is replaced by the new pointer. If an xDelete callback +** was specified along with the original pointer, it is invoked at this +** point. +** +** The xDelete callback, if one is specified, is also invoked on the +** auxiliary data pointer after the FTS5 query has finished. +** +** If an error (e.g. an OOM condition) occurs within this function, +** the auxiliary data is set to NULL and an error code returned. If the +** xDelete parameter was not NULL, it is invoked on the auxiliary data +** pointer before returning. +** +** +** xGetAuxdata(pFts5, bClear) +** +** Returns the current auxiliary data pointer for the fts5 extension +** function. See the xSetAuxdata() method for details. +** +** If the bClear argument is non-zero, then the auxiliary data is cleared +** (set to NULL) before this function returns. In this case the xDelete, +** if any, is not invoked. +** +** +** xRowCount(pFts5, pnRow) +** +** This function is used to retrieve the total number of rows in the table. +** In other words, the same value that would be returned by: +** +** SELECT count(*) FROM ftstable; +** +** xPhraseFirst() +** This function is used, along with type Fts5PhraseIter and the xPhraseNext +** method, to iterate through all instances of a single query phrase within +** the current row. This is the same information as is accessible via the +** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient +** to use, this API may be faster under some circumstances. To iterate +** through instances of phrase iPhrase, use the following code: +** +** Fts5PhraseIter iter; +** int iCol, iOff; +** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); +** iCol>=0; +** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) +** ){ +** // An instance of phrase iPhrase at offset iOff of column iCol +** } +** +** The Fts5PhraseIter structure is defined above. Applications should not +** modify this structure directly - it should only be used as shown above +** with the xPhraseFirst() and xPhraseNext() API methods (and by +** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). +** +** This API can be quite slow if used with an FTS5 table created with the +** "detail=none" or "detail=column" option. If the FTS5 table is created +** with either "detail=none" or "detail=column" and "content=" option +** (i.e. if it is a contentless table), then this API always iterates +** through an empty set (all calls to xPhraseFirst() set iCol to -1). +** +** xPhraseNext() +** See xPhraseFirst above. +** +** xPhraseFirstColumn() +** This function and xPhraseNextColumn() are similar to the xPhraseFirst() +** and xPhraseNext() APIs described above. The difference is that instead +** of iterating through all instances of a phrase in the current row, these +** APIs are used to iterate through the set of columns in the current row +** that contain one or more instances of a specified phrase. For example: +** +** Fts5PhraseIter iter; +** int iCol; +** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); +** iCol>=0; +** pApi->xPhraseNextColumn(pFts, &iter, &iCol) +** ){ +** // Column iCol contains at least one instance of phrase iPhrase +** } +** +** This API can be quite slow if used with an FTS5 table created with the +** "detail=none" option. If the FTS5 table is created with either +** "detail=none" "content=" option (i.e. if it is a contentless table), +** then this API always iterates through an empty set (all calls to +** xPhraseFirstColumn() set iCol to -1). +** +** The information accessed using this API and its companion +** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext +** (or xInst/xInstCount). The chief advantage of this API is that it is +** significantly more efficient than those alternatives when used with +** "detail=column" tables. +** +** xPhraseNextColumn() +** See xPhraseFirstColumn above. +** +** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken) +** This is used to access token iToken of phrase iPhrase of the current +** query. Before returning, output parameter *ppToken is set to point +** to a buffer containing the requested token, and *pnToken to the +** size of this buffer in bytes. +** +** If iPhrase or iToken are less than zero, or if iPhrase is greater than +** or equal to the number of phrases in the query as reported by +** xPhraseCount(), or if iToken is equal to or greater than the number of +** tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken + are both zeroed. +** +** The output text is not a copy of the query text that specified the +** token. It is the output of the tokenizer module. For tokendata=1 +** tables, this includes any embedded 0x00 and trailing data. +** +** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken) +** This is used to access token iToken of phrase hit iIdx within the +** current row. If iIdx is less than zero or greater than or equal to the +** value returned by xInstCount(), SQLITE_RANGE is returned. Otherwise, +** output variable (*ppToken) is set to point to a buffer containing the +** matching document token, and (*pnToken) to the size of that buffer in +** bytes. This API is not available if the specified token matches a +** prefix query term. In that case both output variables are always set +** to 0. +** +** The output text is not a copy of the document text that was tokenized. +** It is the output of the tokenizer module. For tokendata=1 tables, this +** includes any embedded 0x00 and trailing data. +** +** This API can be quite slow if used with an FTS5 table created with the +** "detail=none" or "detail=column" option. +*/ +struct Fts5ExtensionApi { + int iVersion; /* Currently always set to 3 */ + + void *(*xUserData)(Fts5Context*); + + int (*xColumnCount)(Fts5Context*); + int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); + int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); + + int (*xTokenize)(Fts5Context*, + const char *pText, int nText, /* Text to tokenize */ + void *pCtx, /* Context passed to xToken() */ + int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ + ); + + int (*xPhraseCount)(Fts5Context*); + int (*xPhraseSize)(Fts5Context*, int iPhrase); + + int (*xInstCount)(Fts5Context*, int *pnInst); + int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); + + sqlite3_int64 (*xRowid)(Fts5Context*); + int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); + int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); + + int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, + int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) + ); + int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); + void *(*xGetAuxdata)(Fts5Context*, int bClear); + + int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); + void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); + + int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); + void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); + + /* Below this point are iVersion>=3 only */ + int (*xQueryToken)(Fts5Context*, + int iPhrase, int iToken, + const char **ppToken, int *pnToken + ); + int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*); +}; + +/* +** CUSTOM AUXILIARY FUNCTIONS +*************************************************************************/ + +/************************************************************************* +** CUSTOM TOKENIZERS +** +** Applications may also register custom tokenizer types. A tokenizer +** is registered by providing fts5 with a populated instance of the +** following structure. All structure methods must be defined, setting +** any member of the fts5_tokenizer struct to NULL leads to undefined +** behaviour. The structure methods are expected to function as follows: +** +** xCreate: +** This function is used to allocate and initialize a tokenizer instance. +** A tokenizer instance is required to actually tokenize text. +** +** The first argument passed to this function is a copy of the (void*) +** pointer provided by the application when the fts5_tokenizer object +** was registered with FTS5 (the third argument to xCreateTokenizer()). +** The second and third arguments are an array of nul-terminated strings +** containing the tokenizer arguments, if any, specified following the +** tokenizer name as part of the CREATE VIRTUAL TABLE statement used +** to create the FTS5 table. +** +** The final argument is an output variable. If successful, (*ppOut) +** should be set to point to the new tokenizer handle and SQLITE_OK +** returned. If an error occurs, some value other than SQLITE_OK should +** be returned. In this case, fts5 assumes that the final value of *ppOut +** is undefined. +** +** xDelete: +** This function is invoked to delete a tokenizer handle previously +** allocated using xCreate(). Fts5 guarantees that this function will +** be invoked exactly once for each successful call to xCreate(). +** +** xTokenize: +** This function is expected to tokenize the nText byte string indicated +** by argument pText. pText may or may not be nul-terminated. The first +** argument passed to this function is a pointer to an Fts5Tokenizer object +** returned by an earlier call to xCreate(). +** +** The second argument indicates the reason that FTS5 is requesting +** tokenization of the supplied text. This is always one of the following +** four values: +** +**
  • FTS5_TOKENIZE_DOCUMENT - A document is being inserted into +** or removed from the FTS table. The tokenizer is being invoked to +** determine the set of tokens to add to (or delete from) the +** FTS index. +** +**
  • FTS5_TOKENIZE_QUERY - A MATCH query is being executed +** against the FTS index. The tokenizer is being called to tokenize +** a bareword or quoted string specified as part of the query. +** +**
  • (FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX) - Same as +** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is +** followed by a "*" character, indicating that the last token +** returned by the tokenizer will be treated as a token prefix. +** +**
  • FTS5_TOKENIZE_AUX - The tokenizer is being invoked to +** satisfy an fts5_api.xTokenize() request made by an auxiliary +** function. Or an fts5_api.xColumnSize() request made by the same +** on a columnsize=0 database. +**
+** +** For each token in the input string, the supplied callback xToken() must +** be invoked. The first argument to it should be a copy of the pointer +** passed as the second argument to xTokenize(). The third and fourth +** arguments are a pointer to a buffer containing the token text, and the +** size of the token in bytes. The 4th and 5th arguments are the byte offsets +** of the first byte of and first byte immediately following the text from +** which the token is derived within the input. +** +** The second argument passed to the xToken() callback ("tflags") should +** normally be set to 0. The exception is if the tokenizer supports +** synonyms. In this case see the discussion below for details. +** +** FTS5 assumes the xToken() callback is invoked for each token in the +** order that they occur within the input text. +** +** If an xToken() callback returns any value other than SQLITE_OK, then +** the tokenization should be abandoned and the xTokenize() method should +** immediately return a copy of the xToken() return value. Or, if the +** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, +** if an error occurs with the xTokenize() implementation itself, it +** may abandon the tokenization and return any error code other than +** SQLITE_OK or SQLITE_DONE. +** +** SYNONYM SUPPORT +** +** Custom tokenizers may also support synonyms. Consider a case in which a +** user wishes to query for a phrase such as "first place". Using the +** built-in tokenizers, the FTS5 query 'first + place' will match instances +** of "first place" within the document set, but not alternative forms +** such as "1st place". In some applications, it would be better to match +** all instances of "first place" or "1st place" regardless of which form +** the user specified in the MATCH query text. +** +** There are several ways to approach this in FTS5: +** +**
  1. By mapping all synonyms to a single token. In this case, using +** the above example, this means that the tokenizer returns the +** same token for inputs "first" and "1st". Say that token is in +** fact "first", so that when the user inserts the document "I won +** 1st place" entries are added to the index for tokens "i", "won", +** "first" and "place". If the user then queries for '1st + place', +** the tokenizer substitutes "first" for "1st" and the query works +** as expected. +** +**
  2. By querying the index for all synonyms of each query term +** separately. In this case, when tokenizing query text, the +** tokenizer may provide multiple synonyms for a single term +** within the document. FTS5 then queries the index for each +** synonym individually. For example, faced with the query: +** +** +** ... MATCH 'first place' +** +** the tokenizer offers both "1st" and "first" as synonyms for the +** first token in the MATCH query and FTS5 effectively runs a query +** similar to: +** +** +** ... MATCH '(first OR 1st) place' +** +** except that, for the purposes of auxiliary functions, the query +** still appears to contain just two phrases - "(first OR 1st)" +** being treated as a single phrase. +** +**
  3. By adding multiple synonyms for a single term to the FTS index. +** Using this method, when tokenizing document text, the tokenizer +** provides multiple synonyms for each token. So that when a +** document such as "I won first place" is tokenized, entries are +** added to the FTS index for "i", "won", "first", "1st" and +** "place". +** +** This way, even if the tokenizer does not provide synonyms +** when tokenizing query text (it should not - to do so would be +** inefficient), it doesn't matter if the user queries for +** 'first + place' or '1st + place', as there are entries in the +** FTS index corresponding to both forms of the first token. +**
+** +** Whether it is parsing document or query text, any call to xToken that +** specifies a tflags argument with the FTS5_TOKEN_COLOCATED bit +** is considered to supply a synonym for the previous token. For example, +** when parsing the document "I won first place", a tokenizer that supports +** synonyms would call xToken() 5 times, as follows: +** +** +** xToken(pCtx, 0, "i", 1, 0, 1); +** xToken(pCtx, 0, "won", 3, 2, 5); +** xToken(pCtx, 0, "first", 5, 6, 11); +** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); +** xToken(pCtx, 0, "place", 5, 12, 17); +** +** +** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time +** xToken() is called. Multiple synonyms may be specified for a single token +** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. +** There is no limit to the number of synonyms that may be provided for a +** single token. +** +** In many cases, method (1) above is the best approach. It does not add +** extra data to the FTS index or require FTS5 to query for multiple terms, +** so it is efficient in terms of disk space and query speed. However, it +** does not support prefix queries very well. If, as suggested above, the +** token "first" is substituted for "1st" by the tokenizer, then the query: +** +** +** ... MATCH '1s*' +** +** will not match documents that contain the token "1st" (as the tokenizer +** will probably not map "1s" to any prefix of "first"). +** +** For full prefix support, method (3) may be preferred. In this case, +** because the index contains entries for both "first" and "1st", prefix +** queries such as 'fi*' or '1s*' will match correctly. However, because +** extra entries are added to the FTS index, this method uses more space +** within the database. +** +** Method (2) offers a midpoint between (1) and (3). Using this method, +** a query such as '1s*' will match documents that contain the literal +** token "1st", but not "first" (assuming the tokenizer is not able to +** provide synonyms for prefixes). However, a non-prefix query like '1st' +** will match against "1st" and "first". This method does not require +** extra disk space, as no extra entries are added to the FTS index. +** On the other hand, it may require more CPU cycles to run MATCH queries, +** as separate queries of the FTS index are required for each synonym. +** +** When using methods (2) or (3), it is important that the tokenizer only +** provide synonyms when tokenizing document text (method (3)) or query +** text (method (2)), not both. Doing so will not cause any errors, but is +** inefficient. +*/ +typedef struct Fts5Tokenizer Fts5Tokenizer; +typedef struct fts5_tokenizer fts5_tokenizer; +struct fts5_tokenizer { + int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); + void (*xDelete)(Fts5Tokenizer*); + int (*xTokenize)(Fts5Tokenizer*, + void *pCtx, + int flags, /* Mask of FTS5_TOKENIZE_* flags */ + const char *pText, int nText, + int (*xToken)( + void *pCtx, /* Copy of 2nd argument to xTokenize() */ + int tflags, /* Mask of FTS5_TOKEN_* flags */ + const char *pToken, /* Pointer to buffer containing token */ + int nToken, /* Size of token in bytes */ + int iStart, /* Byte offset of token within input text */ + int iEnd /* Byte offset of end of token within input text */ + ) + ); +}; + +/* Flags that may be passed as the third argument to xTokenize() */ +#define FTS5_TOKENIZE_QUERY 0x0001 +#define FTS5_TOKENIZE_PREFIX 0x0002 +#define FTS5_TOKENIZE_DOCUMENT 0x0004 +#define FTS5_TOKENIZE_AUX 0x0008 + +/* Flags that may be passed by the tokenizer implementation back to FTS5 +** as the third argument to the supplied xToken callback. */ +#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ + +/* +** END OF CUSTOM TOKENIZERS +*************************************************************************/ + +/************************************************************************* +** FTS5 EXTENSION REGISTRATION API +*/ +typedef struct fts5_api fts5_api; +struct fts5_api { + int iVersion; /* Currently always set to 2 */ + + /* Create a new tokenizer */ + int (*xCreateTokenizer)( + fts5_api *pApi, + const char *zName, + void *pUserData, + fts5_tokenizer *pTokenizer, + void (*xDestroy)(void*) + ); + + /* Find an existing tokenizer */ + int (*xFindTokenizer)( + fts5_api *pApi, + const char *zName, + void **ppUserData, + fts5_tokenizer *pTokenizer + ); + + /* Create a new auxiliary function */ + int (*xCreateFunction)( + fts5_api *pApi, + const char *zName, + void *pUserData, + fts5_extension_function xFunction, + void (*xDestroy)(void*) + ); +}; + +/* +** END OF REGISTRATION API +*************************************************************************/ + +#ifdef __cplusplus +} /* end of the 'extern "C"' block */ +#endif + +#endif /* _FTS5_H */ + +/******** End of fts5.h *********/ diff --git a/codex-rs/state/vendor/sqlite-recover/sqlite3recover.c b/codex-rs/state/vendor/sqlite-recover/sqlite3recover.c new file mode 100644 index 0000000000..218e1e0e0f --- /dev/null +++ b/codex-rs/state/vendor/sqlite-recover/sqlite3recover.c @@ -0,0 +1,2925 @@ +/* +** 2022-08-27 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** +*/ + + +#include "sqlite3recover.h" +#include +#include + +#ifndef SQLITE_OMIT_VIRTUALTABLE + +/* +** Declaration for public API function in file dbdata.c. This may be called +** with NULL as the final two arguments to register the sqlite_dbptr and +** sqlite_dbdata virtual tables with a database handle. +*/ +#ifdef _WIN32 +__declspec(dllexport) +#endif +int sqlite3_dbdata_init(sqlite3*, char**, const sqlite3_api_routines*); + +typedef unsigned int u32; +typedef unsigned char u8; +typedef sqlite3_int64 i64; + +/* +** Work around C99 "flex-array" syntax for pre-C99 compilers, so as +** to avoid complaints from -fsanitize=strict-bounds. +*/ +#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) +# define FLEXARRAY +#else +# define FLEXARRAY 1 +#endif + +typedef struct RecoverTable RecoverTable; +typedef struct RecoverColumn RecoverColumn; + +/* +** When recovering rows of data that can be associated with table +** definitions recovered from the sqlite_schema table, each table is +** represented by an instance of the following object. +** +** iRoot: +** The root page in the original database. Not necessarily (and usually +** not) the same in the recovered database. +** +** zTab: +** Name of the table. +** +** nCol/aCol[]: +** aCol[] is an array of nCol columns. In the order in which they appear +** in the table. +** +** bIntkey: +** Set to true for intkey tables, false for WITHOUT ROWID. +** +** iRowidBind: +** Each column in the aCol[] array has associated with it the index of +** the bind parameter its values will be bound to in the INSERT statement +** used to construct the output database. If the table does has a rowid +** but not an INTEGER PRIMARY KEY column, then iRowidBind contains the +** index of the bind paramater to which the rowid value should be bound. +** Otherwise, it contains -1. If the table does contain an INTEGER PRIMARY +** KEY column, then the rowid value should be bound to the index associated +** with the column. +** +** pNext: +** All RecoverTable objects used by the recovery operation are allocated +** and populated as part of creating the recovered database schema in +** the output database, before any non-schema data are recovered. They +** are then stored in a singly-linked list linked by this variable beginning +** at sqlite3_recover.pTblList. +*/ +struct RecoverTable { + u32 iRoot; /* Root page in original database */ + char *zTab; /* Name of table */ + int nCol; /* Number of columns in table */ + RecoverColumn *aCol; /* Array of columns */ + int bIntkey; /* True for intkey, false for without rowid */ + int iRowidBind; /* If >0, bind rowid to INSERT here */ + RecoverTable *pNext; +}; + +/* +** Each database column is represented by an instance of the following object +** stored in the RecoverTable.aCol[] array of the associated table. +** +** iField: +** The index of the associated field within database records. Or -1 if +** there is no associated field (e.g. for virtual generated columns). +** +** iBind: +** The bind index of the INSERT statement to bind this columns values +** to. Or 0 if there is no such index (iff (iField<0)). +** +** bIPK: +** True if this is the INTEGER PRIMARY KEY column. +** +** zCol: +** Name of column. +** +** eHidden: +** A RECOVER_EHIDDEN_* constant value (see below for interpretation of each). +*/ +struct RecoverColumn { + int iField; /* Field in record on disk */ + int iBind; /* Binding to use in INSERT */ + int bIPK; /* True for IPK column */ + char *zCol; + int eHidden; +}; + +#define RECOVER_EHIDDEN_NONE 0 /* Normal database column */ +#define RECOVER_EHIDDEN_HIDDEN 1 /* Column is __HIDDEN__ */ +#define RECOVER_EHIDDEN_VIRTUAL 2 /* Virtual generated column */ +#define RECOVER_EHIDDEN_STORED 3 /* Stored generated column */ + +/* +** Bitmap object used to track pages in the input database. Allocated +** and manipulated only by the following functions: +** +** recoverBitmapAlloc() +** recoverBitmapFree() +** recoverBitmapSet() +** recoverBitmapQuery() +** +** nPg: +** Largest page number that may be stored in the bitmap. The range +** of valid keys is 1 to nPg, inclusive. +** +** aElem[]: +** Array large enough to contain a bit for each key. For key value +** iKey, the associated bit is the bit (iKey%32) of aElem[iKey/32]. +** In other words, the following is true if bit iKey is set, or +** false if it is clear: +** +** (aElem[iKey/32] & (1 << (iKey%32))) ? 1 : 0 +*/ +typedef struct RecoverBitmap RecoverBitmap; +struct RecoverBitmap { + i64 nPg; /* Size of bitmap */ + u32 aElem[FLEXARRAY]; /* Array of 32-bit bitmasks */ +}; + +/* Size in bytes of a RecoverBitmap object sufficient to cover 32 pages */ +#define SZ_RECOVERBITMAP_32 (16) + +/* +** State variables (part of the sqlite3_recover structure) used while +** recovering data for tables identified in the recovered schema (state +** RECOVER_STATE_WRITING). +*/ +typedef struct RecoverStateW1 RecoverStateW1; +struct RecoverStateW1 { + sqlite3_stmt *pTbls; + sqlite3_stmt *pSel; + sqlite3_stmt *pInsert; + int nInsert; + + RecoverTable *pTab; /* Table currently being written */ + int nMax; /* Max column count in any schema table */ + sqlite3_value **apVal; /* Array of nMax values */ + int nVal; /* Number of valid entries in apVal[] */ + int bHaveRowid; + i64 iRowid; + i64 iPrevPage; + int iPrevCell; +}; + +/* +** State variables (part of the sqlite3_recover structure) used while +** recovering data destined for the lost and found table (states +** RECOVER_STATE_LOSTANDFOUND[123]). +*/ +typedef struct RecoverStateLAF RecoverStateLAF; +struct RecoverStateLAF { + RecoverBitmap *pUsed; + i64 nPg; /* Size of db in pages */ + sqlite3_stmt *pAllAndParent; + sqlite3_stmt *pMapInsert; + sqlite3_stmt *pMaxField; + sqlite3_stmt *pUsedPages; + sqlite3_stmt *pFindRoot; + sqlite3_stmt *pInsert; /* INSERT INTO lost_and_found ... */ + sqlite3_stmt *pAllPage; + sqlite3_stmt *pPageData; + sqlite3_value **apVal; + int nMaxField; +}; + +/* +** Main recover handle structure. +*/ +struct sqlite3_recover { + /* Copies of sqlite3_recover_init[_sql]() parameters */ + sqlite3 *dbIn; /* Input database */ + char *zDb; /* Name of input db ("main" etc.) */ + char *zUri; /* URI for output database */ + void *pSqlCtx; /* SQL callback context */ + int (*xSql)(void*,const char*); /* Pointer to SQL callback function */ + + /* Values configured by sqlite3_recover_config() */ + char *zStateDb; /* State database to use (or NULL) */ + char *zLostAndFound; /* Name of lost-and-found table (or NULL) */ + int bFreelistCorrupt; /* SQLITE_RECOVER_FREELIST_CORRUPT setting */ + int bRecoverRowid; /* SQLITE_RECOVER_ROWIDS setting */ + int bSlowIndexes; /* SQLITE_RECOVER_SLOWINDEXES setting */ + + int pgsz; + int detected_pgsz; + int nReserve; + u8 *pPage1Disk; + u8 *pPage1Cache; + + /* Error code and error message */ + int errCode; /* For sqlite3_recover_errcode() */ + char *zErrMsg; /* For sqlite3_recover_errmsg() */ + + int eState; + int bCloseTransaction; + + /* Variables used with eState==RECOVER_STATE_WRITING */ + RecoverStateW1 w1; + + /* Variables used with states RECOVER_STATE_LOSTANDFOUND[123] */ + RecoverStateLAF laf; + + /* Fields used within sqlite3_recover_run() */ + sqlite3 *dbOut; /* Output database */ + sqlite3_stmt *pGetPage; /* SELECT against input db sqlite_dbdata */ + RecoverTable *pTblList; /* List of tables recovered from schema */ +}; + +/* +** The various states in which an sqlite3_recover object may exist: +** +** RECOVER_STATE_INIT: +** The object is initially created in this state. sqlite3_recover_step() +** has yet to be called. This is the only state in which it is permitted +** to call sqlite3_recover_config(). +** +** RECOVER_STATE_WRITING: +** +** RECOVER_STATE_LOSTANDFOUND1: +** State to populate the bitmap of pages used by other tables or the +** database freelist. +** +** RECOVER_STATE_LOSTANDFOUND2: +** Populate the recovery.map table - used to figure out a "root" page +** for each lost page from in the database from which records are +** extracted. +** +** RECOVER_STATE_LOSTANDFOUND3: +** Populate the lost-and-found table itself. +*/ +#define RECOVER_STATE_INIT 0 +#define RECOVER_STATE_WRITING 1 +#define RECOVER_STATE_LOSTANDFOUND1 2 +#define RECOVER_STATE_LOSTANDFOUND2 3 +#define RECOVER_STATE_LOSTANDFOUND3 4 +#define RECOVER_STATE_SCHEMA2 5 +#define RECOVER_STATE_DONE 6 + + +/* +** Global variables used by this extension. +*/ +typedef struct RecoverGlobal RecoverGlobal; +struct RecoverGlobal { + const sqlite3_io_methods *pMethods; + sqlite3_recover *p; +}; +static RecoverGlobal recover_g; + +/* +** Use this static SQLite mutex to protect the globals during the +** first call to sqlite3_recover_step(). +*/ +#define RECOVER_MUTEX_ID SQLITE_MUTEX_STATIC_APP2 + + +/* +** Default value for SQLITE_RECOVER_ROWIDS (sqlite3_recover.bRecoverRowid). +*/ +#define RECOVER_ROWID_DEFAULT 1 + +/* +** Mutex handling: +** +** recoverEnterMutex() - Enter the recovery mutex +** recoverLeaveMutex() - Leave the recovery mutex +** recoverAssertMutexHeld() - Assert that the recovery mutex is held +*/ +#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE==0 +# define recoverEnterMutex() +# define recoverLeaveMutex() +#else +static void recoverEnterMutex(void){ + sqlite3_mutex_enter(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)); +} +static void recoverLeaveMutex(void){ + sqlite3_mutex_leave(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)); +} +#endif +#if SQLITE_THREADSAFE+0>=1 && defined(SQLITE_DEBUG) +static void recoverAssertMutexHeld(void){ + assert( sqlite3_mutex_held(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)) ); +} +#else +# define recoverAssertMutexHeld() +#endif + + +/* +** Like strlen(). But handles NULL pointer arguments. +*/ +static int recoverStrlen(const char *zStr){ + if( zStr==0 ) return 0; + return (int)(strlen(zStr)&0x7fffffff); +} + +/* +** This function is a no-op if the recover handle passed as the first +** argument already contains an error (if p->errCode!=SQLITE_OK). +** +** Otherwise, an attempt is made to allocate, zero and return a buffer nByte +** bytes in size. If successful, a pointer to the new buffer is returned. Or, +** if an OOM error occurs, NULL is returned and the handle error code +** (p->errCode) set to SQLITE_NOMEM. +*/ +static void *recoverMalloc(sqlite3_recover *p, i64 nByte){ + void *pRet = 0; + assert( nByte>0 ); + if( p->errCode==SQLITE_OK ){ + pRet = sqlite3_malloc64(nByte); + if( pRet ){ + memset(pRet, 0, nByte); + }else{ + p->errCode = SQLITE_NOMEM; + } + } + return pRet; +} + +/* +** Set the error code and error message for the recover handle passed as +** the first argument. The error code is set to the value of parameter +** errCode. +** +** Parameter zFmt must be a printf() style formatting string. The handle +** error message is set to the result of using any trailing arguments for +** parameter substitutions in the formatting string. +** +** For example: +** +** recoverError(p, SQLITE_ERROR, "no such table: %s", zTablename); +*/ +static int recoverError( + sqlite3_recover *p, + int errCode, + const char *zFmt, ... +){ + char *z = 0; + va_list ap; + va_start(ap, zFmt); + if( zFmt ){ + z = sqlite3_vmprintf(zFmt, ap); + } + va_end(ap); + sqlite3_free(p->zErrMsg); + p->zErrMsg = z; + p->errCode = errCode; + return errCode; +} + + +/* +** This function is a no-op if p->errCode is initially other than SQLITE_OK. +** In this case it returns NULL. +** +** Otherwise, an attempt is made to allocate and return a bitmap object +** large enough to store a bit for all page numbers between 1 and nPg, +** inclusive. The bitmap is initially zeroed. +*/ +static RecoverBitmap *recoverBitmapAlloc(sqlite3_recover *p, i64 nPg){ + int nElem = (nPg+1+31) / 32; + int nByte = SZ_RECOVERBITMAP_32 + nElem*sizeof(u32); + RecoverBitmap *pRet = (RecoverBitmap*)recoverMalloc(p, nByte); + + if( pRet ){ + pRet->nPg = nPg; + } + return pRet; +} + +/* +** Free a bitmap object allocated by recoverBitmapAlloc(). +*/ +static void recoverBitmapFree(RecoverBitmap *pMap){ + sqlite3_free(pMap); +} + +/* +** Set the bit associated with page iPg in bitvec pMap. +*/ +static void recoverBitmapSet(RecoverBitmap *pMap, i64 iPg){ + if( iPg<=pMap->nPg ){ + int iElem = (iPg / 32); + int iBit = (iPg % 32); + pMap->aElem[iElem] |= (((u32)1) << iBit); + } +} + +/* +** Query bitmap object pMap for the state of the bit associated with page +** iPg. Return 1 if it is set, or 0 otherwise. +*/ +static int recoverBitmapQuery(RecoverBitmap *pMap, i64 iPg){ + int ret = 1; + if( iPg<=pMap->nPg && iPg>0 ){ + int iElem = (iPg / 32); + int iBit = (iPg % 32); + ret = (pMap->aElem[iElem] & (((u32)1) << iBit)) ? 1 : 0; + } + return ret; +} + +/* +** Set the recover handle error to the error code and message returned by +** calling sqlite3_errcode() and sqlite3_errmsg(), respectively, on database +** handle db. +*/ +static int recoverDbError(sqlite3_recover *p, sqlite3 *db){ + return recoverError(p, sqlite3_errcode(db), "%s", sqlite3_errmsg(db)); +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). +** +** Otherwise, it attempts to prepare the SQL statement in zSql against +** database handle db. If successful, the statement handle is returned. +** Or, if an error occurs, NULL is returned and an error left in the +** recover handle. +*/ +static sqlite3_stmt *recoverPrepare( + sqlite3_recover *p, + sqlite3 *db, + const char *zSql +){ + sqlite3_stmt *pStmt = 0; + if( p->errCode==SQLITE_OK ){ + if( sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0) ){ + recoverDbError(p, db); + } + } + return pStmt; +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). +** +** Otherwise, argument zFmt is used as a printf() style format string, +** along with any trailing arguments, to create an SQL statement. This +** SQL statement is prepared against database handle db and, if successful, +** the statment handle returned. Or, if an error occurs - either during +** the printf() formatting or when preparing the resulting SQL - an +** error code and message are left in the recover handle. +*/ +static sqlite3_stmt *recoverPreparePrintf( + sqlite3_recover *p, + sqlite3 *db, + const char *zFmt, ... +){ + sqlite3_stmt *pStmt = 0; + if( p->errCode==SQLITE_OK ){ + va_list ap; + char *z; + va_start(ap, zFmt); + z = sqlite3_vmprintf(zFmt, ap); + va_end(ap); + if( z==0 ){ + p->errCode = SQLITE_NOMEM; + }else{ + pStmt = recoverPrepare(p, db, z); + sqlite3_free(z); + } + } + return pStmt; +} + +/* +** Reset SQLite statement handle pStmt. If the call to sqlite3_reset() +** indicates that an error occurred, and there is not already an error +** in the recover handle passed as the first argument, set the error +** code and error message appropriately. +** +** This function returns a copy of the statement handle pointer passed +** as the second argument. +*/ +static sqlite3_stmt *recoverReset(sqlite3_recover *p, sqlite3_stmt *pStmt){ + int rc = sqlite3_reset(pStmt); + if( rc!=SQLITE_OK && rc!=SQLITE_CONSTRAINT && p->errCode==SQLITE_OK ){ + recoverDbError(p, sqlite3_db_handle(pStmt)); + } + return pStmt; +} + +/* +** Finalize SQLite statement handle pStmt. If the call to sqlite3_reset() +** indicates that an error occurred, and there is not already an error +** in the recover handle passed as the first argument, set the error +** code and error message appropriately. +*/ +static void recoverFinalize(sqlite3_recover *p, sqlite3_stmt *pStmt){ + sqlite3 *db = sqlite3_db_handle(pStmt); + int rc = sqlite3_finalize(pStmt); + if( rc!=SQLITE_OK && p->errCode==SQLITE_OK ){ + recoverDbError(p, db); + } +} + +/* +** Run a single SQL statement in zSql. If zSql contains two or more +** SQL statements separated by ';', only the first is run. +** +** Return the sqlite3_finalizer() or sqlite3_prepare() result code +** from running the zSql statement. +*/ +static int recoverOneStmt(sqlite3 *db, const char *zSql){ + sqlite3_stmt *pStmt = 0; + int rc; + if( zSql==0 ) return SQLITE_OK; + rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0); + if( rc ){ + sqlite3_finalize(pStmt); + return rc; + } + while( SQLITE_ROW==sqlite3_step(pStmt) ){} + return sqlite3_finalize(pStmt); +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). A copy of p->errCode is returned in this +** case. +** +** Otherwise, execute a single SQL statment in zSql. Even if zSql contains +** two or more SQL statements separated by ';', only execute the first one. +** If successful, return SQLITE_OK. Or, if an error occurs, leave an error +** code and message in the recover handle and return a copy of the error code. +*/ +static int recoverExec(sqlite3_recover *p, sqlite3 *db, const char *zSql){ + if( p->errCode==SQLITE_OK ){ + int rc = recoverOneStmt(db, zSql); + if( rc ){ + recoverDbError(p, db); + } + } + return p->errCode; +} + +/* +** Bind the value pVal to parameter iBind of statement pStmt. Leave an +** error in the recover handle passed as the first argument if an error +** (e.g. an OOM) occurs. +*/ +static void recoverBindValue( + sqlite3_recover *p, + sqlite3_stmt *pStmt, + int iBind, + sqlite3_value *pVal +){ + if( p->errCode==SQLITE_OK ){ + int rc = sqlite3_bind_value(pStmt, iBind, pVal); + if( rc ) recoverError(p, rc, 0); + } +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). NULL is returned in this case. +** +** Otherwise, an attempt is made to interpret zFmt as a printf() style +** formatting string and the result of using the trailing arguments for +** parameter substitution with it written into a buffer obtained from +** sqlite3_malloc(). If successful, a pointer to the buffer is returned. +** It is the responsibility of the caller to eventually free the buffer +** using sqlite3_free(). +** +** Or, if an error occurs, an error code and message is left in the recover +** handle and NULL returned. +*/ +static char *recoverMPrintf(sqlite3_recover *p, const char *zFmt, ...){ + va_list ap; + char *z; + va_start(ap, zFmt); + z = sqlite3_vmprintf(zFmt, ap); + va_end(ap); + if( p->errCode==SQLITE_OK ){ + if( z==0 ) p->errCode = SQLITE_NOMEM; + }else{ + sqlite3_free(z); + z = 0; + } + return z; +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). Zero is returned in this case. +** +** Otherwise, execute "PRAGMA page_count" against the input database. If +** successful, return the integer result. Or, if an error occurs, leave an +** error code and error message in the sqlite3_recover handle and return +** zero. +*/ +static i64 recoverPageCount(sqlite3_recover *p){ + i64 nPg = 0; + if( p->errCode==SQLITE_OK ){ + sqlite3_stmt *pStmt = 0; + pStmt = recoverPreparePrintf(p, p->dbIn, "PRAGMA %Q.page_count", p->zDb); + if( pStmt ){ + sqlite3_step(pStmt); + nPg = sqlite3_column_int64(pStmt, 0); + } + recoverFinalize(p, pStmt); + } + return nPg; +} + +/* +** Implementation of SQL scalar function "read_i32". The first argument to +** this function must be a blob. The second a non-negative integer. This +** function reads and returns a 32-bit big-endian integer from byte +** offset (4*) of the blob. +** +** SELECT read_i32(, ) +*/ +static void recoverReadI32( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + const unsigned char *pBlob; + int nBlob; + int iInt; + + assert( argc==2 ); + nBlob = sqlite3_value_bytes(argv[0]); + pBlob = (const unsigned char*)sqlite3_value_blob(argv[0]); + iInt = sqlite3_value_int(argv[1]) & 0xFFFF; + + if( (iInt+1)*4<=nBlob ){ + const unsigned char *a = &pBlob[iInt*4]; + i64 iVal = ((i64)a[0]<<24) + + ((i64)a[1]<<16) + + ((i64)a[2]<< 8) + + ((i64)a[3]<< 0); + sqlite3_result_int64(context, iVal); + } +} + +/* +** Implementation of SQL scalar function "page_is_used". This function +** is used as part of the procedure for locating orphan rows for the +** lost-and-found table, and it depends on those routines having populated +** the sqlite3_recover.laf.pUsed variable. +** +** The only argument to this function is a page-number. It returns true +** if the page has already been used somehow during data recovery, or false +** otherwise. +** +** SELECT page_is_used(); +*/ +static void recoverPageIsUsed( + sqlite3_context *pCtx, + int nArg, + sqlite3_value **apArg +){ + sqlite3_recover *p = (sqlite3_recover*)sqlite3_user_data(pCtx); + i64 pgno = sqlite3_value_int64(apArg[0]); + assert( nArg==1 ); + sqlite3_result_int(pCtx, recoverBitmapQuery(p->laf.pUsed, pgno)); +} + +/* +** The implementation of a user-defined SQL function invoked by the +** sqlite_dbdata and sqlite_dbptr virtual table modules to access pages +** of the database being recovered. +** +** This function always takes a single integer argument. If the argument +** is zero, then the value returned is the number of pages in the db being +** recovered. If the argument is greater than zero, it is a page number. +** The value returned in this case is an SQL blob containing the data for +** the identified page of the db being recovered. e.g. +** +** SELECT getpage(0); -- return number of pages in db +** SELECT getpage(4); -- return page 4 of db as a blob of data +*/ +static void recoverGetPage( + sqlite3_context *pCtx, + int nArg, + sqlite3_value **apArg +){ + sqlite3_recover *p = (sqlite3_recover*)sqlite3_user_data(pCtx); + i64 pgno = sqlite3_value_int64(apArg[0]); + sqlite3_stmt *pStmt = 0; + + assert( nArg==1 ); + if( pgno==0 ){ + i64 nPg = recoverPageCount(p); + sqlite3_result_int64(pCtx, nPg); + return; + }else{ + if( p->pGetPage==0 ){ + pStmt = p->pGetPage = recoverPreparePrintf( + p, p->dbIn, "SELECT data FROM sqlite_dbpage(%Q) WHERE pgno=?", p->zDb + ); + }else if( p->errCode==SQLITE_OK ){ + pStmt = p->pGetPage; + } + + if( pStmt ){ + sqlite3_bind_int64(pStmt, 1, pgno); + if( SQLITE_ROW==sqlite3_step(pStmt) ){ + const u8 *aPg; + int nPg; + assert( p->errCode==SQLITE_OK ); + aPg = sqlite3_column_blob(pStmt, 0); + nPg = sqlite3_column_bytes(pStmt, 0); + if( pgno==1 && nPg==p->pgsz && 0==memcmp(p->pPage1Cache, aPg, nPg) ){ + aPg = p->pPage1Disk; + } + sqlite3_result_blob(pCtx, aPg, nPg-p->nReserve, SQLITE_TRANSIENT); + } + recoverReset(p, pStmt); + } + } + + if( p->errCode ){ + if( p->zErrMsg ) sqlite3_result_error(pCtx, p->zErrMsg, -1); + sqlite3_result_error_code(pCtx, p->errCode); + } +} + +/* +** Find a string that is not found anywhere in z[]. Return a pointer +** to that string. +** +** Try to use zA and zB first. If both of those are already found in z[] +** then make up some string and store it in the buffer zBuf. +*/ +static const char *recoverUnusedString( + const char *z, /* Result must not appear anywhere in z */ + const char *zA, const char *zB, /* Try these first */ + char *zBuf /* Space to store a generated string */ +){ + unsigned i = 0; + if( strstr(z, zA)==0 ) return zA; + if( strstr(z, zB)==0 ) return zB; + do{ + sqlite3_snprintf(20,zBuf,"(%s%u)", zA, i++); + }while( strstr(z,zBuf)!=0 ); + return zBuf; +} + +/* +** Implementation of scalar SQL function "escape_crlf". The argument passed to +** this function is the output of built-in function quote(). If the first +** character of the input is "'", indicating that the value passed to quote() +** was a text value, then this function searches the input for "\n" and "\r" +** characters and adds a wrapper similar to the following: +** +** replace(replace(, '\n', char(10), '\r', char(13)); +** +** Or, if the first character of the input is not "'", then a copy of the input +** is returned. +*/ +static void recoverEscapeCrlf( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + const char *zText = (const char*)sqlite3_value_text(argv[0]); + (void)argc; + if( zText && zText[0]=='\'' ){ + int nText = sqlite3_value_bytes(argv[0]); + int i; + char zBuf1[20]; + char zBuf2[20]; + const char *zNL = 0; + const char *zCR = 0; + int nCR = 0; + int nNL = 0; + + for(i=0; zText[i]; i++){ + if( zNL==0 && zText[i]=='\n' ){ + zNL = recoverUnusedString(zText, "\\n", "\\012", zBuf1); + nNL = (int)strlen(zNL); + } + if( zCR==0 && zText[i]=='\r' ){ + zCR = recoverUnusedString(zText, "\\r", "\\015", zBuf2); + nCR = (int)strlen(zCR); + } + } + + if( zNL || zCR ){ + int iOut = 0; + i64 nMax = (nNL > nCR) ? nNL : nCR; + i64 nAlloc = nMax * nText + (nMax+64)*2; + char *zOut = (char*)sqlite3_malloc64(nAlloc); + if( zOut==0 ){ + sqlite3_result_error_nomem(context); + return; + } + + if( zNL && zCR ){ + memcpy(&zOut[iOut], "replace(replace(", 16); + iOut += 16; + }else{ + memcpy(&zOut[iOut], "replace(", 8); + iOut += 8; + } + for(i=0; zText[i]; i++){ + if( zText[i]=='\n' ){ + memcpy(&zOut[iOut], zNL, nNL); + iOut += nNL; + }else if( zText[i]=='\r' ){ + memcpy(&zOut[iOut], zCR, nCR); + iOut += nCR; + }else{ + zOut[iOut] = zText[i]; + iOut++; + } + } + + if( zNL ){ + memcpy(&zOut[iOut], ",'", 2); iOut += 2; + memcpy(&zOut[iOut], zNL, nNL); iOut += nNL; + memcpy(&zOut[iOut], "', char(10))", 12); iOut += 12; + } + if( zCR ){ + memcpy(&zOut[iOut], ",'", 2); iOut += 2; + memcpy(&zOut[iOut], zCR, nCR); iOut += nCR; + memcpy(&zOut[iOut], "', char(13))", 12); iOut += 12; + } + + sqlite3_result_text(context, zOut, iOut, SQLITE_TRANSIENT); + sqlite3_free(zOut); + return; + } + } + + sqlite3_result_value(context, argv[0]); +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). A copy of the error code is returned in +** this case. +** +** Otherwise, attempt to populate temporary table "recovery.schema" with the +** parts of the database schema that can be extracted from the input database. +** +** If no error occurs, SQLITE_OK is returned. Otherwise, an error code +** and error message are left in the recover handle and a copy of the +** error code returned. It is not considered an error if part of all of +** the database schema cannot be recovered due to corruption. +*/ +static int recoverCacheSchema(sqlite3_recover *p){ + return recoverExec(p, p->dbOut, + "WITH RECURSIVE pages(p) AS (" + " SELECT 1" + " UNION" + " SELECT child FROM sqlite_dbptr('getpage()'), pages WHERE pgno=p" + ")" + "INSERT INTO recovery.schema SELECT" + " max(CASE WHEN field=0 THEN value ELSE NULL END)," + " max(CASE WHEN field=1 THEN value ELSE NULL END)," + " max(CASE WHEN field=2 THEN value ELSE NULL END)," + " max(CASE WHEN field=3 THEN value ELSE NULL END)," + " max(CASE WHEN field=4 THEN value ELSE NULL END)" + "FROM sqlite_dbdata('getpage()') WHERE pgno IN (" + " SELECT p FROM pages" + ") GROUP BY pgno, cell" + ); +} + +/* +** If this recover handle is not in SQL callback mode (i.e. was not created +** using sqlite3_recover_init_sql()) of if an error has already occurred, +** this function is a no-op. Otherwise, issue a callback with SQL statement +** zSql as the parameter. +** +** If the callback returns non-zero, set the recover handle error code to +** the value returned (so that the caller will abandon processing). +*/ +static void recoverSqlCallback(sqlite3_recover *p, const char *zSql){ + if( p->errCode==SQLITE_OK && p->xSql ){ + int res = p->xSql(p->pSqlCtx, zSql); + if( res ){ + recoverError(p, SQLITE_ERROR, "callback returned an error - %d", res); + } + } +} + +/* +** Transfer the following settings from the input database to the output +** database: +** +** + page-size, +** + auto-vacuum settings, +** + database encoding, +** + user-version (PRAGMA user_version), and +** + application-id (PRAGMA application_id), and +*/ +static void recoverTransferSettings(sqlite3_recover *p){ + const char *aPragma[] = { + "encoding", + "page_size", + "auto_vacuum", + "user_version", + "application_id" + }; + int ii; + + /* Truncate the output database to 0 pages in size. This is done by + ** opening a new, empty, temp db, then using the backup API to clobber + ** any existing output db with a copy of it. */ + if( p->errCode==SQLITE_OK ){ + sqlite3 *db2 = 0; + int rc = sqlite3_open("", &db2); + if( rc!=SQLITE_OK ){ + recoverDbError(p, db2); + return; + } + + for(ii=0; ii<(int)(sizeof(aPragma)/sizeof(aPragma[0])); ii++){ + const char *zPrag = aPragma[ii]; + sqlite3_stmt *p1 = 0; + p1 = recoverPreparePrintf(p, p->dbIn, "PRAGMA %Q.%s", p->zDb, zPrag); + if( p->errCode==SQLITE_OK && sqlite3_step(p1)==SQLITE_ROW ){ + const char *zArg = (const char*)sqlite3_column_text(p1, 0); + char *z2 = recoverMPrintf(p, "PRAGMA %s = %Q", zPrag, zArg); + recoverSqlCallback(p, z2); + recoverExec(p, db2, z2); + sqlite3_free(z2); + if( zArg==0 ){ + recoverError(p, SQLITE_NOMEM, 0); + } + } + recoverFinalize(p, p1); + } + recoverExec(p, db2, "CREATE TABLE t1(a)"); + recoverExec(p, db2, "DROP TABLE t1"); + + if( p->errCode==SQLITE_OK ){ + sqlite3 *db = p->dbOut; + sqlite3_backup *pBackup = sqlite3_backup_init(db, "main", db2, "main"); + if( pBackup ){ + sqlite3_backup_step(pBackup, -1); + p->errCode = sqlite3_backup_finish(pBackup); + }else{ + recoverDbError(p, db); + } + } + + sqlite3_close(db2); + } +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). A copy of the error code is returned in +** this case. +** +** Otherwise, an attempt is made to open the output database, attach +** and create the schema of the temporary database used to store +** intermediate data, and to register all required user functions and +** virtual table modules with the output handle. +** +** If no error occurs, SQLITE_OK is returned. Otherwise, an error code +** and error message are left in the recover handle and a copy of the +** error code returned. +*/ +static int recoverOpenOutput(sqlite3_recover *p){ + struct Func { + const char *zName; + int nArg; + void (*xFunc)(sqlite3_context*,int,sqlite3_value **); + } aFunc[] = { + { "getpage", 1, recoverGetPage }, + { "page_is_used", 1, recoverPageIsUsed }, + { "read_i32", 2, recoverReadI32 }, + { "escape_crlf", 1, recoverEscapeCrlf }, + }; + + const int flags = SQLITE_OPEN_URI|SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE; + sqlite3 *db = 0; /* New database handle */ + int ii; /* For iterating through aFunc[] */ + + assert( p->dbOut==0 ); + + if( sqlite3_open_v2(p->zUri, &db, flags, 0) ){ + recoverDbError(p, db); + } + + /* Register the sqlite_dbdata and sqlite_dbptr virtual table modules. + ** These two are registered with the output database handle - this + ** module depends on the input handle supporting the sqlite_dbpage + ** virtual table only. */ + if( p->errCode==SQLITE_OK ){ + p->errCode = sqlite3_dbdata_init(db, 0, 0); + } + + /* Register the custom user-functions with the output handle. */ + for(ii=0; + p->errCode==SQLITE_OK && ii<(int)(sizeof(aFunc)/sizeof(aFunc[0])); + ii++){ + p->errCode = sqlite3_create_function(db, aFunc[ii].zName, + aFunc[ii].nArg, SQLITE_UTF8, (void*)p, aFunc[ii].xFunc, 0, 0 + ); + } + + p->dbOut = db; + return p->errCode; +} + +/* +** Attach the auxiliary database 'recovery' to the output database handle. +** This temporary database is used during the recovery process and then +** discarded. +*/ +static void recoverOpenRecovery(sqlite3_recover *p){ + char *zSql = recoverMPrintf(p, "ATTACH %Q AS recovery;", p->zStateDb); + recoverExec(p, p->dbOut, zSql); + sqlite3_free(zSql); + recoverExec(p, p->dbOut, "PRAGMA writable_schema = 1"); + recoverExec(p, p->dbOut, + "CREATE TABLE recovery.map(pgno INTEGER PRIMARY KEY, parent INT)"); + recoverExec(p, p->dbOut, + "CREATE TABLE recovery.schema(type, name, tbl_name, rootpage, sql)"); +} + + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). +** +** Otherwise, argument zName must be the name of a table that has just been +** created in the output database. This function queries the output db +** for the schema of said table, and creates a RecoverTable object to +** store the schema in memory. The new RecoverTable object is linked into +** the list at sqlite3_recover.pTblList. +** +** Parameter iRoot must be the root page of table zName in the INPUT +** database. +*/ +static void recoverAddTable( + sqlite3_recover *p, + const char *zName, /* Name of table created in output db */ + i64 iRoot /* Root page of same table in INPUT db */ +){ + sqlite3_stmt *pStmt = recoverPreparePrintf(p, p->dbOut, + "PRAGMA table_xinfo(%Q)", zName + ); + + if( pStmt ){ + int iPk = -1; + int iBind = 1; + RecoverTable *pNew = 0; + int nCol = 0; + int nName = recoverStrlen(zName); + int nByte = 0; + while( sqlite3_step(pStmt)==SQLITE_ROW ){ + nCol++; + nByte += (sqlite3_column_bytes(pStmt, 1)+1); + } + nByte += sizeof(RecoverTable) + nCol*sizeof(RecoverColumn) + nName+1; + recoverReset(p, pStmt); + + pNew = recoverMalloc(p, nByte); + if( pNew ){ + int i = 0; + int iField = 0; + char *csr = 0; + pNew->aCol = (RecoverColumn*)&pNew[1]; + pNew->zTab = csr = (char*)&pNew->aCol[nCol]; + pNew->nCol = nCol; + pNew->iRoot = iRoot; + memcpy(csr, zName, nName); + csr += nName+1; + + for(i=0; sqlite3_step(pStmt)==SQLITE_ROW; i++){ + int iPKF = sqlite3_column_int(pStmt, 5); + int n = sqlite3_column_bytes(pStmt, 1); + const char *z = (const char*)sqlite3_column_text(pStmt, 1); + const char *zType = (const char*)sqlite3_column_text(pStmt, 2); + int eHidden = sqlite3_column_int(pStmt, 6); + + if( iPk==-1 && iPKF==1 && !sqlite3_stricmp("integer", zType) ) iPk = i; + if( iPKF>1 ) iPk = -2; + pNew->aCol[i].zCol = csr; + pNew->aCol[i].eHidden = eHidden; + if( eHidden==RECOVER_EHIDDEN_VIRTUAL ){ + pNew->aCol[i].iField = -1; + }else{ + pNew->aCol[i].iField = iField++; + } + if( eHidden!=RECOVER_EHIDDEN_VIRTUAL + && eHidden!=RECOVER_EHIDDEN_STORED + ){ + pNew->aCol[i].iBind = iBind++; + } + memcpy(csr, z, n); + csr += (n+1); + } + + pNew->pNext = p->pTblList; + p->pTblList = pNew; + pNew->bIntkey = 1; + } + + recoverFinalize(p, pStmt); + + pStmt = recoverPreparePrintf(p, p->dbOut, "PRAGMA index_xinfo(%Q)", zName); + while( pStmt && sqlite3_step(pStmt)==SQLITE_ROW ){ + int iField = sqlite3_column_int(pStmt, 0); + int iCol = sqlite3_column_int(pStmt, 1); + + assert( iColnCol ); + pNew->aCol[iCol].iField = iField; + + pNew->bIntkey = 0; + iPk = -2; + } + recoverFinalize(p, pStmt); + + if( p->errCode==SQLITE_OK ){ + if( iPk>=0 ){ + pNew->aCol[iPk].bIPK = 1; + }else if( pNew->bIntkey ){ + pNew->iRowidBind = iBind++; + } + } + } +} + +/* +** This function is called after recoverCacheSchema() has cached those parts +** of the input database schema that could be recovered in temporary table +** "recovery.schema". This function creates in the output database copies +** of all parts of that schema that must be created before the tables can +** be populated. Specifically, this means: +** +** * all tables that are not VIRTUAL, and +** * UNIQUE indexes. +** +** If the recovery handle uses SQL callbacks, then callbacks containing +** the associated "CREATE TABLE" and "CREATE INDEX" statements are made. +** +** Additionally, records are added to the sqlite_schema table of the +** output database for any VIRTUAL tables. The CREATE VIRTUAL TABLE +** records are written directly to sqlite_schema, not actually executed. +** If the handle is in SQL callback mode, then callbacks are invoked +** with equivalent SQL statements. +*/ +static int recoverWriteSchema1(sqlite3_recover *p){ + sqlite3_stmt *pSelect = 0; + sqlite3_stmt *pTblname = 0; + + pSelect = recoverPrepare(p, p->dbOut, + "WITH dbschema(rootpage, name, sql, tbl, isVirtual, isIndex) AS (" + " SELECT rootpage, name, sql, " + " type='table', " + " sql LIKE 'create virtual%'," + " (type='index' AND (sql LIKE '%unique%' OR ?1))" + " FROM recovery.schema" + ")" + "SELECT rootpage, tbl, isVirtual, name, sql" + " FROM dbschema " + " WHERE (tbl OR isIndex) AND sql GLOB 'CREATE *'" + " ORDER BY tbl DESC, name=='sqlite_sequence' DESC" + ); + + pTblname = recoverPrepare(p, p->dbOut, + "SELECT name FROM sqlite_schema " + "WHERE type='table' ORDER BY rowid DESC LIMIT 1" + ); + + if( pSelect ){ + sqlite3_bind_int(pSelect, 1, p->bSlowIndexes); + while( sqlite3_step(pSelect)==SQLITE_ROW ){ + i64 iRoot = sqlite3_column_int64(pSelect, 0); + int bTable = sqlite3_column_int(pSelect, 1); + int bVirtual = sqlite3_column_int(pSelect, 2); + const char *zName = (const char*)sqlite3_column_text(pSelect, 3); + const char *zSql = (const char*)sqlite3_column_text(pSelect, 4); + char *zFree = 0; + int rc = SQLITE_OK; + + if( bVirtual ){ + zSql = (const char*)(zFree = recoverMPrintf(p, + "INSERT INTO sqlite_schema VALUES('table', %Q, %Q, 0, %Q)", + zName, zName, zSql + )); + } + rc = recoverOneStmt(p->dbOut, zSql); + if( rc==SQLITE_OK ){ + recoverSqlCallback(p, zSql); + if( bTable && !bVirtual ){ + if( SQLITE_ROW==sqlite3_step(pTblname) ){ + const char *zTbl = (const char*)sqlite3_column_text(pTblname, 0); + if( zTbl ) recoverAddTable(p, zTbl, iRoot); + } + recoverReset(p, pTblname); + } + }else if( rc!=SQLITE_ERROR ){ + recoverDbError(p, p->dbOut); + } + sqlite3_free(zFree); + } + } + recoverFinalize(p, pSelect); + recoverFinalize(p, pTblname); + + return p->errCode; +} + +/* +** This function is called after the output database has been populated. It +** adds all recovered schema elements that were not created in the output +** database by recoverWriteSchema1() - everything except for tables and +** UNIQUE indexes. Specifically: +** +** * views, +** * triggers, +** * non-UNIQUE indexes. +** +** If the recover handle is in SQL callback mode, then equivalent callbacks +** are issued to create the schema elements. +*/ +static int recoverWriteSchema2(sqlite3_recover *p){ + sqlite3_stmt *pSelect = 0; + + pSelect = recoverPrepare(p, p->dbOut, + p->bSlowIndexes ? + "SELECT rootpage, sql FROM recovery.schema " + " WHERE type!='table' AND type!='index'" + " AND sql GLOB 'CREATE *'" + : + "SELECT rootpage, sql FROM recovery.schema " + " WHERE type!='table' AND (type!='index' OR sql NOT LIKE '%unique%')" + " AND sql GLOB 'CREATE *'" + ); + + if( pSelect ){ + while( sqlite3_step(pSelect)==SQLITE_ROW ){ + const char *zSql = (const char*)sqlite3_column_text(pSelect, 1); + int rc = recoverOneStmt(p->dbOut, zSql); + if( rc==SQLITE_OK ){ + recoverSqlCallback(p, zSql); + }else if( rc!=SQLITE_ERROR ){ + recoverDbError(p, p->dbOut); + } + } + } + recoverFinalize(p, pSelect); + + return p->errCode; +} + +/* +** This function is a no-op if recover handle p already contains an error +** (if p->errCode!=SQLITE_OK). In this case it returns NULL. +** +** Otherwise, if the recover handle is configured to create an output +** database (was created by sqlite3_recover_init()), then this function +** prepares and returns an SQL statement to INSERT a new record into table +** pTab, assuming the first nField fields of a record extracted from disk +** are valid. +** +** For example, if table pTab is: +** +** CREATE TABLE name(a, b GENERATED ALWAYS AS (a+1) STORED, c, d, e); +** +** And nField is 4, then the SQL statement prepared and returned is: +** +** INSERT INTO (a, c, d) VALUES (?1, ?2, ?3); +** +** In this case even though 4 values were extracted from the input db, +** only 3 are written to the output, as the generated STORED column +** cannot be written. +** +** If the recover handle is in SQL callback mode, then the SQL statement +** prepared is such that evaluating it returns a single row containing +** a single text value - itself an SQL statement similar to the above, +** except with SQL literals in place of the variables. For example: +** +** SELECT 'INSERT INTO (a, c, d) VALUES (' +** || quote(?1) || ', ' +** || quote(?2) || ', ' +** || quote(?3) || ')'; +** +** In either case, it is the responsibility of the caller to eventually +** free the statement handle using sqlite3_finalize(). +*/ +static sqlite3_stmt *recoverInsertStmt( + sqlite3_recover *p, + RecoverTable *pTab, + int nField +){ + sqlite3_stmt *pRet = 0; + const char *zSep = ""; + const char *zSqlSep = ""; + char *zSql = 0; + char *zFinal = 0; + char *zBind = 0; + int ii; + int bSql = p->xSql ? 1 : 0; + + if( nField<=0 ) return 0; + + assert( nField<=pTab->nCol ); + + zSql = recoverMPrintf(p, "INSERT OR IGNORE INTO %Q(", pTab->zTab); + + if( pTab->iRowidBind ){ + assert( pTab->bIntkey ); + zSql = recoverMPrintf(p, "%z_rowid_", zSql); + if( bSql ){ + zBind = recoverMPrintf(p, "%zquote(?%d)", zBind, pTab->iRowidBind); + }else{ + zBind = recoverMPrintf(p, "%z?%d", zBind, pTab->iRowidBind); + } + zSqlSep = "||', '||"; + zSep = ", "; + } + + for(ii=0; iiaCol[ii].eHidden; + if( eHidden!=RECOVER_EHIDDEN_VIRTUAL + && eHidden!=RECOVER_EHIDDEN_STORED + ){ + assert( pTab->aCol[ii].iField>=0 && pTab->aCol[ii].iBind>=1 ); + zSql = recoverMPrintf(p, "%z%s%Q", zSql, zSep, pTab->aCol[ii].zCol); + + if( bSql ){ + zBind = recoverMPrintf(p, + "%z%sescape_crlf(quote(?%d))", zBind, zSqlSep, pTab->aCol[ii].iBind + ); + zSqlSep = "||', '||"; + }else{ + zBind = recoverMPrintf(p, "%z%s?%d", zBind, zSep, pTab->aCol[ii].iBind); + } + zSep = ", "; + } + } + + if( bSql ){ + zFinal = recoverMPrintf(p, "SELECT %Q || ') VALUES (' || %s || ')'", + zSql, zBind + ); + }else{ + zFinal = recoverMPrintf(p, "%s) VALUES (%s)", zSql, zBind); + } + + pRet = recoverPrepare(p, p->dbOut, zFinal); + sqlite3_free(zSql); + sqlite3_free(zBind); + sqlite3_free(zFinal); + + return pRet; +} + + +/* +** Search the list of RecoverTable objects at p->pTblList for one that +** has root page iRoot in the input database. If such an object is found, +** return a pointer to it. Otherwise, return NULL. +*/ +static RecoverTable *recoverFindTable(sqlite3_recover *p, u32 iRoot){ + RecoverTable *pRet = 0; + for(pRet=p->pTblList; pRet && pRet->iRoot!=iRoot; pRet=pRet->pNext); + return pRet; +} + +/* +** This function attempts to create a lost and found table within the +** output db. If successful, it returns a pointer to a buffer containing +** the name of the new table. It is the responsibility of the caller to +** eventually free this buffer using sqlite3_free(). +** +** If an error occurs, NULL is returned and an error code and error +** message left in the recover handle. +*/ +static char *recoverLostAndFoundCreate( + sqlite3_recover *p, /* Recover object */ + int nField /* Number of column fields in new table */ +){ + char *zTbl = 0; + sqlite3_stmt *pProbe = 0; + int ii = 0; + + pProbe = recoverPrepare(p, p->dbOut, + "SELECT 1 FROM sqlite_schema WHERE name=?" + ); + for(ii=-1; zTbl==0 && p->errCode==SQLITE_OK && ii<1000; ii++){ + int bFail = 0; + if( ii<0 ){ + zTbl = recoverMPrintf(p, "%s", p->zLostAndFound); + }else{ + zTbl = recoverMPrintf(p, "%s_%d", p->zLostAndFound, ii); + } + + if( p->errCode==SQLITE_OK ){ + sqlite3_bind_text(pProbe, 1, zTbl, -1, SQLITE_STATIC); + if( SQLITE_ROW==sqlite3_step(pProbe) ){ + bFail = 1; + } + recoverReset(p, pProbe); + } + + if( bFail ){ + sqlite3_clear_bindings(pProbe); + sqlite3_free(zTbl); + zTbl = 0; + } + } + recoverFinalize(p, pProbe); + + if( zTbl ){ + const char *zSep = 0; + char *zField = 0; + char *zSql = 0; + + zSep = "rootpgno INTEGER, pgno INTEGER, nfield INTEGER, id INTEGER, "; + for(ii=0; p->errCode==SQLITE_OK && iidbOut, zSql); + recoverSqlCallback(p, zSql); + sqlite3_free(zSql); + }else if( p->errCode==SQLITE_OK ){ + recoverError( + p, SQLITE_ERROR, "failed to create %s output table", p->zLostAndFound + ); + } + + return zTbl; +} + +/* +** Synthesize and prepare an INSERT statement to write to the lost_and_found +** table in the output database. The name of the table is zTab, and it has +** nField c* fields. +*/ +static sqlite3_stmt *recoverLostAndFoundInsert( + sqlite3_recover *p, + const char *zTab, + int nField +){ + int nTotal = nField + 4; + int ii; + char *zBind = 0; + sqlite3_stmt *pRet = 0; + + if( p->xSql==0 ){ + for(ii=0; iidbOut, "INSERT INTO %s VALUES(%s)", zTab, zBind + ); + }else{ + const char *zSep = ""; + for(ii=0; iidbOut, "SELECT 'INSERT INTO %s VALUES(' || %s || ')'", zTab, zBind + ); + } + + sqlite3_free(zBind); + return pRet; +} + +/* +** Input database page iPg contains data that will be written to the +** lost-and-found table of the output database. This function attempts +** to identify the root page of the tree that page iPg belonged to. +** If successful, it sets output variable (*piRoot) to the page number +** of the root page and returns SQLITE_OK. Otherwise, if an error occurs, +** an SQLite error code is returned and the final value of *piRoot +** undefined. +*/ +static int recoverLostAndFoundFindRoot( + sqlite3_recover *p, + i64 iPg, + i64 *piRoot +){ + RecoverStateLAF *pLaf = &p->laf; + + if( pLaf->pFindRoot==0 ){ + pLaf->pFindRoot = recoverPrepare(p, p->dbOut, + "WITH RECURSIVE p(pgno) AS (" + " SELECT ?" + " UNION" + " SELECT parent FROM recovery.map AS m, p WHERE m.pgno=p.pgno" + ") " + "SELECT p.pgno FROM p, recovery.map m WHERE m.pgno=p.pgno " + " AND m.parent IS NULL" + ); + } + if( p->errCode==SQLITE_OK ){ + sqlite3_bind_int64(pLaf->pFindRoot, 1, iPg); + if( sqlite3_step(pLaf->pFindRoot)==SQLITE_ROW ){ + *piRoot = sqlite3_column_int64(pLaf->pFindRoot, 0); + }else{ + *piRoot = iPg; + } + recoverReset(p, pLaf->pFindRoot); + } + return p->errCode; +} + +/* +** Recover data from page iPage of the input database and write it to +** the lost-and-found table in the output database. +*/ +static void recoverLostAndFoundOnePage(sqlite3_recover *p, i64 iPage){ + RecoverStateLAF *pLaf = &p->laf; + sqlite3_value **apVal = pLaf->apVal; + sqlite3_stmt *pPageData = pLaf->pPageData; + sqlite3_stmt *pInsert = pLaf->pInsert; + + int nVal = -1; + int iPrevCell = 0; + i64 iRoot = 0; + int bHaveRowid = 0; + i64 iRowid = 0; + int ii = 0; + + if( recoverLostAndFoundFindRoot(p, iPage, &iRoot) ) return; + sqlite3_bind_int64(pPageData, 1, iPage); + while( p->errCode==SQLITE_OK && SQLITE_ROW==sqlite3_step(pPageData) ){ + int iCell = sqlite3_column_int64(pPageData, 0); + int iField = sqlite3_column_int64(pPageData, 1); + + if( iPrevCell!=iCell && nVal>=0 ){ + /* Insert the new row */ + sqlite3_bind_int64(pInsert, 1, iRoot); /* rootpgno */ + sqlite3_bind_int64(pInsert, 2, iPage); /* pgno */ + sqlite3_bind_int(pInsert, 3, nVal); /* nfield */ + if( bHaveRowid ){ + sqlite3_bind_int64(pInsert, 4, iRowid); /* id */ + } + for(ii=0; iinMaxField ){ + sqlite3_value *pVal = sqlite3_column_value(pPageData, 2); + apVal[iField] = sqlite3_value_dup(pVal); + assert( iField==nVal || (nVal==-1 && iField==0) ); + nVal = iField+1; + if( apVal[iField]==0 ){ + recoverError(p, SQLITE_NOMEM, 0); + } + } + + iPrevCell = iCell; + } + recoverReset(p, pPageData); + + for(ii=0; iilaf; + if( p->errCode==SQLITE_OK ){ + if( pLaf->pInsert==0 ){ + return SQLITE_DONE; + }else{ + if( p->errCode==SQLITE_OK ){ + int res = sqlite3_step(pLaf->pAllPage); + if( res==SQLITE_ROW ){ + i64 iPage = sqlite3_column_int64(pLaf->pAllPage, 0); + if( recoverBitmapQuery(pLaf->pUsed, iPage)==0 ){ + recoverLostAndFoundOnePage(p, iPage); + } + }else{ + recoverReset(p, pLaf->pAllPage); + return SQLITE_DONE; + } + } + } + } + return SQLITE_OK; +} + +/* +** Initialize resources required in RECOVER_STATE_LOSTANDFOUND3 +** state - during which the lost-and-found table of the output database +** is populated with recovered data that can not be assigned to any +** recovered schema object. +*/ +static void recoverLostAndFound3Init(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + + if( pLaf->nMaxField>0 ){ + char *zTab = 0; /* Name of lost_and_found table */ + + zTab = recoverLostAndFoundCreate(p, pLaf->nMaxField); + pLaf->pInsert = recoverLostAndFoundInsert(p, zTab, pLaf->nMaxField); + sqlite3_free(zTab); + + pLaf->pAllPage = recoverPreparePrintf(p, p->dbOut, + "WITH RECURSIVE seq(ii) AS (" + " SELECT 1 UNION ALL SELECT ii+1 FROM seq WHERE ii<%lld" + ")" + "SELECT ii FROM seq" , p->laf.nPg + ); + pLaf->pPageData = recoverPrepare(p, p->dbOut, + "SELECT cell, field, value " + "FROM sqlite_dbdata('getpage()') d WHERE d.pgno=? " + "UNION ALL " + "SELECT -1, -1, -1" + ); + + pLaf->apVal = (sqlite3_value**)recoverMalloc(p, + pLaf->nMaxField*sizeof(sqlite3_value*) + ); + } +} + +/* +** Initialize resources required in RECOVER_STATE_WRITING state - during which +** tables recovered from the schema of the input database are populated with +** recovered data. +*/ +static int recoverWriteDataInit(sqlite3_recover *p){ + RecoverStateW1 *p1 = &p->w1; + RecoverTable *pTbl = 0; + int nByte = 0; + + /* Figure out the maximum number of columns for any table in the schema */ + assert( p1->nMax==0 ); + for(pTbl=p->pTblList; pTbl; pTbl=pTbl->pNext){ + if( pTbl->nCol>p1->nMax ) p1->nMax = pTbl->nCol; + } + + /* Allocate an array of (sqlite3_value*) in which to accumulate the values + ** that will be written to the output database in a single row. */ + nByte = sizeof(sqlite3_value*) * (p1->nMax+1); + p1->apVal = (sqlite3_value**)recoverMalloc(p, nByte); + if( p1->apVal==0 ) return p->errCode; + + /* Prepare the SELECT to loop through schema tables (pTbls) and the SELECT + ** to loop through cells that appear to belong to a single table (pSel). */ + p1->pTbls = recoverPrepare(p, p->dbOut, + "SELECT rootpage FROM recovery.schema " + " WHERE type='table' AND (sql NOT LIKE 'create virtual%')" + " ORDER BY (tbl_name='sqlite_sequence') ASC" + ); + p1->pSel = recoverPrepare(p, p->dbOut, + "WITH RECURSIVE pages(page) AS (" + " SELECT ?1" + " UNION" + " SELECT child FROM sqlite_dbptr('getpage()'), pages " + " WHERE pgno=page" + ") " + "SELECT page, cell, field, value " + "FROM sqlite_dbdata('getpage()') d, pages p WHERE p.page=d.pgno " + "UNION ALL " + "SELECT 0, 0, 0, 0" + ); + + return p->errCode; +} + +/* +** Clean up resources allocated by recoverWriteDataInit() (stuff in +** sqlite3_recover.w1). +*/ +static void recoverWriteDataCleanup(sqlite3_recover *p){ + RecoverStateW1 *p1 = &p->w1; + int ii; + for(ii=0; iinVal; ii++){ + sqlite3_value_free(p1->apVal[ii]); + } + sqlite3_free(p1->apVal); + recoverFinalize(p, p1->pInsert); + recoverFinalize(p, p1->pTbls); + recoverFinalize(p, p1->pSel); + memset(p1, 0, sizeof(*p1)); +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_WRITING state - during which tables recovered from the +** schema of the input database are populated with recovered data. +*/ +static int recoverWriteDataStep(sqlite3_recover *p){ + RecoverStateW1 *p1 = &p->w1; + sqlite3_stmt *pSel = p1->pSel; + sqlite3_value **apVal = p1->apVal; + + if( p->errCode==SQLITE_OK && p1->pTab==0 ){ + if( sqlite3_step(p1->pTbls)==SQLITE_ROW ){ + i64 iRoot = sqlite3_column_int64(p1->pTbls, 0); + p1->pTab = recoverFindTable(p, iRoot); + + recoverFinalize(p, p1->pInsert); + p1->pInsert = 0; + + /* If this table is unknown, return early. The caller will invoke this + ** function again and it will move on to the next table. */ + if( p1->pTab==0 ) return p->errCode; + + /* If this is the sqlite_sequence table, delete any rows added by + ** earlier INSERT statements on tables with AUTOINCREMENT primary + ** keys before recovering its contents. The p1->pTbls SELECT statement + ** is rigged to deliver "sqlite_sequence" last of all, so we don't + ** worry about it being modified after it is recovered. */ + if( sqlite3_stricmp("sqlite_sequence", p1->pTab->zTab)==0 ){ + recoverExec(p, p->dbOut, "DELETE FROM sqlite_sequence"); + recoverSqlCallback(p, "DELETE FROM sqlite_sequence"); + } + + /* Bind the root page of this table within the original database to + ** SELECT statement p1->pSel. The SELECT statement will then iterate + ** through cells that look like they belong to table pTab. */ + sqlite3_bind_int64(pSel, 1, iRoot); + + p1->nVal = 0; + p1->bHaveRowid = 0; + p1->iPrevPage = -1; + p1->iPrevCell = -1; + }else{ + return SQLITE_DONE; + } + } + assert( p->errCode!=SQLITE_OK || p1->pTab ); + + if( p->errCode==SQLITE_OK && sqlite3_step(pSel)==SQLITE_ROW ){ + RecoverTable *pTab = p1->pTab; + + i64 iPage = sqlite3_column_int64(pSel, 0); + int iCell = sqlite3_column_int(pSel, 1); + int iField = sqlite3_column_int(pSel, 2); + sqlite3_value *pVal = sqlite3_column_value(pSel, 3); + int bNewCell = (p1->iPrevPage!=iPage || p1->iPrevCell!=iCell); + + assert( bNewCell==0 || (iField==-1 || iField==0) ); + assert( bNewCell || iField==p1->nVal || p1->nVal==pTab->nCol ); + + if( bNewCell ){ + int ii = 0; + if( p1->nVal>=0 ){ + if( p1->pInsert==0 || p1->nVal!=p1->nInsert ){ + recoverFinalize(p, p1->pInsert); + p1->pInsert = recoverInsertStmt(p, pTab, p1->nVal); + p1->nInsert = p1->nVal; + } + if( p1->nVal>0 ){ + sqlite3_stmt *pInsert = p1->pInsert; + for(ii=0; iinCol; ii++){ + RecoverColumn *pCol = &pTab->aCol[ii]; + int iBind = pCol->iBind; + if( iBind>0 ){ + if( pCol->bIPK ){ + sqlite3_bind_int64(pInsert, iBind, p1->iRowid); + }else if( pCol->iFieldnVal ){ + recoverBindValue(p, pInsert, iBind, apVal[pCol->iField]); + } + } + } + if( p->bRecoverRowid && pTab->iRowidBind>0 && p1->bHaveRowid ){ + sqlite3_bind_int64(pInsert, pTab->iRowidBind, p1->iRowid); + } + if( SQLITE_ROW==sqlite3_step(pInsert) ){ + const char *z = (const char*)sqlite3_column_text(pInsert, 0); + recoverSqlCallback(p, z); + } + recoverReset(p, pInsert); + assert( p->errCode || pInsert ); + if( pInsert ) sqlite3_clear_bindings(pInsert); + } + } + + for(ii=0; iinVal; ii++){ + sqlite3_value_free(apVal[ii]); + apVal[ii] = 0; + } + p1->nVal = -1; + p1->bHaveRowid = 0; + } + + if( iPage!=0 ){ + if( iField<0 ){ + p1->iRowid = sqlite3_column_int64(pSel, 3); + assert( p1->nVal==-1 ); + p1->nVal = 0; + p1->bHaveRowid = 1; + }else if( iFieldnCol ){ + assert( apVal[iField]==0 ); + apVal[iField] = sqlite3_value_dup( pVal ); + if( apVal[iField]==0 ){ + recoverError(p, SQLITE_NOMEM, 0); + } + p1->nVal = iField+1; + }else if( pTab->nCol==0 ){ + p1->nVal = pTab->nCol; + } + p1->iPrevCell = iCell; + p1->iPrevPage = iPage; + } + }else{ + recoverReset(p, pSel); + p1->pTab = 0; + } + + return p->errCode; +} + +/* +** Initialize resources required by sqlite3_recover_step() in +** RECOVER_STATE_LOSTANDFOUND1 state - during which the set of pages not +** already allocated to a recovered schema element is determined. +*/ +static void recoverLostAndFound1Init(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + sqlite3_stmt *pStmt = 0; + + assert( p->laf.pUsed==0 ); + pLaf->nPg = recoverPageCount(p); + pLaf->pUsed = recoverBitmapAlloc(p, pLaf->nPg); + + /* Prepare a statement to iterate through all pages that are part of any tree + ** in the recoverable part of the input database schema to the bitmap. And, + ** if !p->bFreelistCorrupt, add all pages that appear to be part of the + ** freelist. */ + pStmt = recoverPrepare( + p, p->dbOut, + "WITH trunk(pgno) AS (" + " SELECT read_i32(getpage(1), 8) AS x WHERE x>0" + " UNION" + " SELECT read_i32(getpage(trunk.pgno), 0) AS x FROM trunk WHERE x>0" + ")," + "trunkdata(pgno, data) AS (" + " SELECT pgno, getpage(pgno) FROM trunk" + ")," + "freelist(data, n, freepgno) AS (" + " SELECT data, min(16384, read_i32(data, 1)-1), pgno FROM trunkdata" + " UNION ALL" + " SELECT data, n-1, read_i32(data, 2+n) FROM freelist WHERE n>=0" + ")," + "" + "roots(r) AS (" + " SELECT 1 UNION ALL" + " SELECT rootpage FROM recovery.schema WHERE rootpage>0" + ")," + "used(page) AS (" + " SELECT r FROM roots" + " UNION" + " SELECT child FROM sqlite_dbptr('getpage()'), used " + " WHERE pgno=page" + ") " + "SELECT page FROM used" + " UNION ALL " + "SELECT freepgno FROM freelist WHERE NOT ?" + ); + if( pStmt ) sqlite3_bind_int(pStmt, 1, p->bFreelistCorrupt); + pLaf->pUsedPages = pStmt; +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_LOSTANDFOUND1 state - during which the set of pages not +** already allocated to a recovered schema element is determined. +*/ +static int recoverLostAndFound1Step(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + int rc = p->errCode; + if( rc==SQLITE_OK ){ + rc = sqlite3_step(pLaf->pUsedPages); + if( rc==SQLITE_ROW ){ + i64 iPg = sqlite3_column_int64(pLaf->pUsedPages, 0); + recoverBitmapSet(pLaf->pUsed, iPg); + rc = SQLITE_OK; + }else{ + recoverFinalize(p, pLaf->pUsedPages); + pLaf->pUsedPages = 0; + } + } + return rc; +} + +/* +** Initialize resources required by RECOVER_STATE_LOSTANDFOUND2 +** state - during which the pages identified in RECOVER_STATE_LOSTANDFOUND1 +** are sorted into sets that likely belonged to the same database tree. +*/ +static void recoverLostAndFound2Init(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + + assert( p->laf.pAllAndParent==0 ); + assert( p->laf.pMapInsert==0 ); + assert( p->laf.pMaxField==0 ); + assert( p->laf.nMaxField==0 ); + + pLaf->pMapInsert = recoverPrepare(p, p->dbOut, + "INSERT OR IGNORE INTO recovery.map(pgno, parent) VALUES(?, ?)" + ); + pLaf->pAllAndParent = recoverPreparePrintf(p, p->dbOut, + "WITH RECURSIVE seq(ii) AS (" + " SELECT 1 UNION ALL SELECT ii+1 FROM seq WHERE ii<%lld" + ")" + "SELECT pgno, child FROM sqlite_dbptr('getpage()') " + " UNION ALL " + "SELECT NULL, ii FROM seq", p->laf.nPg + ); + pLaf->pMaxField = recoverPreparePrintf(p, p->dbOut, + "SELECT max(field)+1 FROM sqlite_dbdata('getpage') WHERE pgno = ?" + ); +} + +/* +** Perform one step (sqlite3_recover_step()) of work for the connection +** passed as the only argument, which is guaranteed to be in +** RECOVER_STATE_LOSTANDFOUND2 state - during which the pages identified +** in RECOVER_STATE_LOSTANDFOUND1 are sorted into sets that likely belonged +** to the same database tree. +*/ +static int recoverLostAndFound2Step(sqlite3_recover *p){ + RecoverStateLAF *pLaf = &p->laf; + if( p->errCode==SQLITE_OK ){ + int res = sqlite3_step(pLaf->pAllAndParent); + if( res==SQLITE_ROW ){ + i64 iChild = sqlite3_column_int(pLaf->pAllAndParent, 1); + if( recoverBitmapQuery(pLaf->pUsed, iChild)==0 ){ + sqlite3_bind_int64(pLaf->pMapInsert, 1, iChild); + sqlite3_bind_value(pLaf->pMapInsert, 2, + sqlite3_column_value(pLaf->pAllAndParent, 0) + ); + sqlite3_step(pLaf->pMapInsert); + recoverReset(p, pLaf->pMapInsert); + sqlite3_bind_int64(pLaf->pMaxField, 1, iChild); + if( SQLITE_ROW==sqlite3_step(pLaf->pMaxField) ){ + int nMax = sqlite3_column_int(pLaf->pMaxField, 0); + if( nMax>pLaf->nMaxField ) pLaf->nMaxField = nMax; + } + recoverReset(p, pLaf->pMaxField); + } + }else{ + recoverFinalize(p, pLaf->pAllAndParent); + pLaf->pAllAndParent =0; + return SQLITE_DONE; + } + } + return p->errCode; +} + +/* +** Free all resources allocated as part of sqlite3_recover_step() calls +** in one of the RECOVER_STATE_LOSTANDFOUND[123] states. +*/ +static void recoverLostAndFoundCleanup(sqlite3_recover *p){ + recoverBitmapFree(p->laf.pUsed); + p->laf.pUsed = 0; + sqlite3_finalize(p->laf.pUsedPages); + sqlite3_finalize(p->laf.pAllAndParent); + sqlite3_finalize(p->laf.pMapInsert); + sqlite3_finalize(p->laf.pMaxField); + sqlite3_finalize(p->laf.pFindRoot); + sqlite3_finalize(p->laf.pInsert); + sqlite3_finalize(p->laf.pAllPage); + sqlite3_finalize(p->laf.pPageData); + p->laf.pUsedPages = 0; + p->laf.pAllAndParent = 0; + p->laf.pMapInsert = 0; + p->laf.pMaxField = 0; + p->laf.pFindRoot = 0; + p->laf.pInsert = 0; + p->laf.pAllPage = 0; + p->laf.pPageData = 0; + sqlite3_free(p->laf.apVal); + p->laf.apVal = 0; +} + +/* +** Free all resources allocated as part of sqlite3_recover_step() calls. +*/ +static void recoverFinalCleanup(sqlite3_recover *p){ + RecoverTable *pTab = 0; + RecoverTable *pNext = 0; + + recoverWriteDataCleanup(p); + recoverLostAndFoundCleanup(p); + + for(pTab=p->pTblList; pTab; pTab=pNext){ + pNext = pTab->pNext; + sqlite3_free(pTab); + } + p->pTblList = 0; + sqlite3_finalize(p->pGetPage); + p->pGetPage = 0; + sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_RESET_CACHE, 0); + + { +#ifndef NDEBUG + int res = +#endif + sqlite3_close(p->dbOut); + assert( res==SQLITE_OK ); + } + p->dbOut = 0; +} + +/* +** Decode and return an unsigned 16-bit big-endian integer value from +** buffer a[]. +*/ +static u32 recoverGetU16(const u8 *a){ + return (((u32)a[0])<<8) + ((u32)a[1]); +} + +/* +** Decode and return an unsigned 32-bit big-endian integer value from +** buffer a[]. +*/ +static u32 recoverGetU32(const u8 *a){ + return (((u32)a[0])<<24) + (((u32)a[1])<<16) + (((u32)a[2])<<8) + ((u32)a[3]); +} + +/* +** Decode an SQLite varint from buffer a[]. Write the decoded value to (*pVal) +** and return the number of bytes consumed. +*/ +static int recoverGetVarint(const u8 *a, i64 *pVal){ + sqlite3_uint64 u = 0; + int i; + for(i=0; i<8; i++){ + u = (u<<7) + (a[i]&0x7f); + if( (a[i]&0x80)==0 ){ *pVal = (sqlite3_int64)u; return i+1; } + } + u = (u<<8) + (a[i]&0xff); + *pVal = (sqlite3_int64)u; + return 9; +} + +/* +** The second argument points to a buffer n bytes in size. If this buffer +** or a prefix thereof appears to contain a well-formed SQLite b-tree page, +** return the page-size in bytes. Otherwise, if the buffer does not +** appear to contain a well-formed b-tree page, return 0. +*/ +static int recoverIsValidPage(u8 *aTmp, const u8 *a, int n){ + u8 *aUsed = aTmp; + int nFrag = 0; + int nActual = 0; + int iFree = 0; + int nCell = 0; /* Number of cells on page */ + int iCellOff = 0; /* Offset of cell array in page */ + int iContent = 0; + int eType = 0; + int ii = 0; + + eType = (int)a[0]; + if( eType!=0x02 && eType!=0x05 && eType!=0x0A && eType!=0x0D ) return 0; + + iFree = (int)recoverGetU16(&a[1]); + nCell = (int)recoverGetU16(&a[3]); + iContent = (int)recoverGetU16(&a[5]); + if( iContent==0 ) iContent = 65536; + nFrag = (int)a[7]; + + if( iContent>n ) return 0; + + memset(aUsed, 0, n); + memset(aUsed, 0xFF, iContent); + + /* Follow the free-list. This is the same format for all b-tree pages. */ + if( iFree && iFree<=iContent ) return 0; + while( iFree ){ + int iNext = 0; + int nByte = 0; + if( iFree>(n-4) ) return 0; + iNext = recoverGetU16(&a[iFree]); + nByte = recoverGetU16(&a[iFree+2]); + if( iFree+nByte>n || nByte<4 ) return 0; + if( iNext && iNextiContent ) return 0; + for(ii=0; iin ){ + return 0; + } + if( eType==0x05 || eType==0x02 ) nByte += 4; + nByte += recoverGetVarint(&a[iOff+nByte], &nPayload); + if( eType==0x0D ){ + i64 dummy = 0; + nByte += recoverGetVarint(&a[iOff+nByte], &dummy); + } + if( eType!=0x05 ){ + int X = (eType==0x0D) ? n-35 : (((n-12)*64/255)-23); + int M = ((n-12)*32/255)-23; + int K = M+((nPayload-M)%(n-4)); + + if( nPayloadn ){ + return 0; + } + for(iByte=iOff; iByte<(iOff+nByte); iByte++){ + if( aUsed[iByte]!=0 ){ + return 0; + } + aUsed[iByte] = 0xFF; + } + } + + nActual = 0; + for(ii=0; iipMethods!=&recover_methods ); + return pFd->pMethods->xClose(pFd); +} + +/* +** Write value v to buffer a[] as a 16-bit big-endian unsigned integer. +*/ +static void recoverPutU16(u8 *a, u32 v){ + a[0] = (v>>8) & 0x00FF; + a[1] = (v>>0) & 0x00FF; +} + +/* +** Write value v to buffer a[] as a 32-bit big-endian unsigned integer. +*/ +static void recoverPutU32(u8 *a, u32 v){ + a[0] = (v>>24) & 0x00FF; + a[1] = (v>>16) & 0x00FF; + a[2] = (v>>8) & 0x00FF; + a[3] = (v>>0) & 0x00FF; +} + +/* +** Detect the page-size of the database opened by file-handle pFd by +** searching the first part of the file for a well-formed SQLite b-tree +** page. If parameter nReserve is non-zero, then as well as searching for +** a b-tree page with zero reserved bytes, this function searches for one +** with nReserve reserved bytes at the end of it. +** +** If successful, set variable p->detected_pgsz to the detected page-size +** in bytes and return SQLITE_OK. Or, if no error occurs but no valid page +** can be found, return SQLITE_OK but leave p->detected_pgsz set to 0. Or, +** if an error occurs (e.g. an IO or OOM error), then an SQLite error code +** is returned. The final value of p->detected_pgsz is undefined in this +** case. +*/ +static int recoverVfsDetectPagesize( + sqlite3_recover *p, /* Recover handle */ + sqlite3_file *pFd, /* File-handle open on input database */ + u32 nReserve, /* Possible nReserve value */ + i64 nSz /* Size of database file in bytes */ +){ + int rc = SQLITE_OK; + const int nMin = 512; + const int nMax = 65536; + const int nMaxBlk = 4; + u32 pgsz = 0; + int iBlk = 0; + u8 *aPg = 0; + u8 *aTmp = 0; + int nBlk = 0; + + aPg = (u8*)sqlite3_malloc(2*nMax); + if( aPg==0 ) return SQLITE_NOMEM; + aTmp = &aPg[nMax]; + + nBlk = (nSz+nMax-1)/nMax; + if( nBlk>nMaxBlk ) nBlk = nMaxBlk; + + do { + for(iBlk=0; rc==SQLITE_OK && iBlk=((iBlk+1)*nMax)) ? nMax : (nSz % nMax); + memset(aPg, 0, nMax); + rc = pFd->pMethods->xRead(pFd, aPg, nByte, iBlk*nMax); + if( rc==SQLITE_OK ){ + int pgsz2; + for(pgsz2=(pgsz ? pgsz*2 : nMin); pgsz2<=nMax; pgsz2=pgsz2*2){ + int iOff; + for(iOff=0; iOff(u32)p->detected_pgsz ){ + p->detected_pgsz = pgsz; + p->nReserve = nReserve; + } + if( nReserve==0 ) break; + nReserve = 0; + }while( 1 ); + + p->detected_pgsz = pgsz; + sqlite3_free(aPg); + return rc; +} + +/* +** The xRead() method of the wrapper VFS. This is used to intercept calls +** to read page 1 of the input database. +*/ +static int recoverVfsRead(sqlite3_file *pFd, void *aBuf, int nByte, i64 iOff){ + int rc = SQLITE_OK; + if( pFd->pMethods==&recover_methods ){ + pFd->pMethods = recover_g.pMethods; + rc = pFd->pMethods->xRead(pFd, aBuf, nByte, iOff); + if( nByte==16 ){ + sqlite3_randomness(16, aBuf); + }else + if( rc==SQLITE_OK && iOff==0 && nByte>=108 ){ + /* Ensure that the database has a valid header file. The only fields + ** that really matter to recovery are: + ** + ** + Database page size (16-bits at offset 16) + ** + Size of db in pages (32-bits at offset 28) + ** + Database encoding (32-bits at offset 56) + ** + ** Also preserved are: + ** + ** + first freelist page (32-bits at offset 32) + ** + size of freelist (32-bits at offset 36) + ** + the wal-mode flags (16-bits at offset 18) + ** + ** We also try to preserve the auto-vacuum, incr-value, user-version + ** and application-id fields - all 32 bit quantities at offsets + ** 52, 60, 64 and 68. All other fields are set to known good values. + ** + ** Byte offset 105 should also contain the page-size as a 16-bit + ** integer. + */ + const int aPreserve[] = {32, 36, 52, 60, 64, 68}; + u8 aHdr[108] = { + 0x53, 0x51, 0x4c, 0x69, 0x74, 0x65, 0x20, 0x66, + 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x20, 0x33, 0x00, + 0xFF, 0xFF, 0x01, 0x01, 0x00, 0x40, 0x20, 0x20, + 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, + 0x00, 0x00, 0x10, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x2e, 0x5b, 0x30, + + 0x0D, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x00 + }; + u8 *a = (u8*)aBuf; + + u32 pgsz = recoverGetU16(&a[16]); + u32 nReserve = a[20]; + u32 enc = recoverGetU32(&a[56]); + u32 dbsz = 0; + i64 dbFileSize = 0; + int ii; + sqlite3_recover *p = recover_g.p; + + if( pgsz==0x01 ) pgsz = 65536; + rc = pFd->pMethods->xFileSize(pFd, &dbFileSize); + + if( rc==SQLITE_OK && p->detected_pgsz==0 ){ + rc = recoverVfsDetectPagesize(p, pFd, nReserve, dbFileSize); + } + if( p->detected_pgsz ){ + pgsz = p->detected_pgsz; + nReserve = p->nReserve; + } + + if( pgsz ){ + dbsz = dbFileSize / pgsz; + } + if( enc!=SQLITE_UTF8 && enc!=SQLITE_UTF16BE && enc!=SQLITE_UTF16LE ){ + enc = SQLITE_UTF8; + } + + sqlite3_free(p->pPage1Cache); + p->pPage1Cache = 0; + p->pPage1Disk = 0; + + p->pgsz = nByte; + p->pPage1Cache = (u8*)recoverMalloc(p, nByte*2); + if( p->pPage1Cache ){ + p->pPage1Disk = &p->pPage1Cache[nByte]; + memcpy(p->pPage1Disk, aBuf, nByte); + aHdr[18] = a[18]; + aHdr[19] = a[19]; + recoverPutU32(&aHdr[28], dbsz); + recoverPutU32(&aHdr[56], enc); + recoverPutU16(&aHdr[105], pgsz-nReserve); + if( pgsz==65536 ) pgsz = 1; + recoverPutU16(&aHdr[16], pgsz); + aHdr[20] = nReserve; + for(ii=0; ii<(int)(sizeof(aPreserve)/sizeof(aPreserve[0])); ii++){ + memcpy(&aHdr[aPreserve[ii]], &a[aPreserve[ii]], 4); + } + memcpy(aBuf, aHdr, sizeof(aHdr)); + memset(&((u8*)aBuf)[sizeof(aHdr)], 0, nByte-sizeof(aHdr)); + + memcpy(p->pPage1Cache, aBuf, nByte); + }else{ + rc = p->errCode; + } + + } + pFd->pMethods = &recover_methods; + }else{ + rc = pFd->pMethods->xRead(pFd, aBuf, nByte, iOff); + } + return rc; +} + +/* +** Used to make sqlite3_io_methods wrapper methods less verbose. +*/ +#define RECOVER_VFS_WRAPPER(code) \ + int rc = SQLITE_OK; \ + if( pFd->pMethods==&recover_methods ){ \ + pFd->pMethods = recover_g.pMethods; \ + rc = code; \ + pFd->pMethods = &recover_methods; \ + }else{ \ + rc = code; \ + } \ + return rc; + +/* +** Methods of the wrapper VFS. All methods except for xRead() and xClose() +** simply uninstall the sqlite3_io_methods wrapper, invoke the equivalent +** method on the lower level VFS, then reinstall the wrapper before returning. +** Those that return an integer value use the RECOVER_VFS_WRAPPER macro. +*/ +static int recoverVfsWrite( + sqlite3_file *pFd, const void *aBuf, int nByte, i64 iOff +){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xWrite(pFd, aBuf, nByte, iOff) + ); +} +static int recoverVfsTruncate(sqlite3_file *pFd, sqlite3_int64 size){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xTruncate(pFd, size) + ); +} +static int recoverVfsSync(sqlite3_file *pFd, int flags){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xSync(pFd, flags) + ); +} +static int recoverVfsFileSize(sqlite3_file *pFd, sqlite3_int64 *pSize){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xFileSize(pFd, pSize) + ); +} +static int recoverVfsLock(sqlite3_file *pFd, int eLock){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xLock(pFd, eLock) + ); +} +static int recoverVfsUnlock(sqlite3_file *pFd, int eLock){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xUnlock(pFd, eLock) + ); +} +static int recoverVfsCheckReservedLock(sqlite3_file *pFd, int *pResOut){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xCheckReservedLock(pFd, pResOut) + ); +} +static int recoverVfsFileControl(sqlite3_file *pFd, int op, void *pArg){ + RECOVER_VFS_WRAPPER ( + (pFd->pMethods ? pFd->pMethods->xFileControl(pFd, op, pArg) : SQLITE_NOTFOUND) + ); +} +static int recoverVfsSectorSize(sqlite3_file *pFd){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xSectorSize(pFd) + ); +} +static int recoverVfsDeviceCharacteristics(sqlite3_file *pFd){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xDeviceCharacteristics(pFd) + ); +} +static int recoverVfsShmMap( + sqlite3_file *pFd, int iPg, int pgsz, int bExtend, void volatile **pp +){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xShmMap(pFd, iPg, pgsz, bExtend, pp) + ); +} +static int recoverVfsShmLock(sqlite3_file *pFd, int offset, int n, int flags){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xShmLock(pFd, offset, n, flags) + ); +} +static void recoverVfsShmBarrier(sqlite3_file *pFd){ + if( pFd->pMethods==&recover_methods ){ + pFd->pMethods = recover_g.pMethods; + pFd->pMethods->xShmBarrier(pFd); + pFd->pMethods = &recover_methods; + }else{ + pFd->pMethods->xShmBarrier(pFd); + } +} +static int recoverVfsShmUnmap(sqlite3_file *pFd, int deleteFlag){ + RECOVER_VFS_WRAPPER ( + pFd->pMethods->xShmUnmap(pFd, deleteFlag) + ); +} + +static int recoverVfsFetch( + sqlite3_file *pFd, + sqlite3_int64 iOff, + int iAmt, + void **pp +){ + (void)pFd; + (void)iOff; + (void)iAmt; + *pp = 0; + return SQLITE_OK; +} +static int recoverVfsUnfetch(sqlite3_file *pFd, sqlite3_int64 iOff, void *p){ + (void)pFd; + (void)iOff; + (void)p; + return SQLITE_OK; +} + +/* +** Install the VFS wrapper around the file-descriptor open on the input +** database for recover handle p. Mutex RECOVER_MUTEX_ID must be held +** when this function is called. +*/ +static void recoverInstallWrapper(sqlite3_recover *p){ + sqlite3_file *pFd = 0; + assert( recover_g.pMethods==0 ); + recoverAssertMutexHeld(); + sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_FILE_POINTER, (void*)&pFd); + assert( pFd==0 || pFd->pMethods!=&recover_methods ); + if( pFd && pFd->pMethods ){ + int iVersion = 1 + (pFd->pMethods->iVersion>1 && pFd->pMethods->xShmMap!=0); + recover_g.pMethods = pFd->pMethods; + recover_g.p = p; + recover_methods.iVersion = iVersion; + pFd->pMethods = &recover_methods; + } +} + +/* +** Uninstall the VFS wrapper that was installed around the file-descriptor open +** on the input database for recover handle p. Mutex RECOVER_MUTEX_ID must be +** held when this function is called. +*/ +static void recoverUninstallWrapper(sqlite3_recover *p){ + sqlite3_file *pFd = 0; + recoverAssertMutexHeld(); + sqlite3_file_control(p->dbIn, p->zDb,SQLITE_FCNTL_FILE_POINTER,(void*)&pFd); + if( pFd && pFd->pMethods ){ + pFd->pMethods = recover_g.pMethods; + recover_g.pMethods = 0; + recover_g.p = 0; + } +} + +/* +** This function does the work of a single sqlite3_recover_step() call. It +** is guaranteed that the handle is not in an error state when this +** function is called. +*/ +static void recoverStep(sqlite3_recover *p){ + assert( p && p->errCode==SQLITE_OK ); + switch( p->eState ){ + case RECOVER_STATE_INIT: { + int bUseWrapper = 1; + /* This is the very first call to sqlite3_recover_step() on this object. + */ + recoverSqlCallback(p, "BEGIN"); + recoverSqlCallback(p, "PRAGMA writable_schema = on"); + recoverSqlCallback(p, "PRAGMA foreign_keys = off"); + + recoverEnterMutex(); + + /* Open the output database. And register required virtual tables and + ** user functions with the new handle. */ + recoverOpenOutput(p); + + /* Attempt to open a transaction and read page 1 of the input database. + ** Two attempts may be made - one with a wrapper installed to ensure + ** that the database header is sane, and then if that attempt returns + ** SQLITE_NOTADB, then again with no wrapper. The second attempt is + ** required for encrypted databases. */ + if( p->errCode==SQLITE_OK ){ + do{ + p->errCode = SQLITE_OK; + if( bUseWrapper ) recoverInstallWrapper(p); + + /* Open a transaction on the input database. */ + sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_RESET_CACHE, 0); + recoverExec(p, p->dbIn, "PRAGMA writable_schema = on"); + recoverExec(p, p->dbIn, "BEGIN"); + if( p->errCode==SQLITE_OK ) p->bCloseTransaction = 1; + recoverExec(p, p->dbIn, "SELECT 1 FROM sqlite_schema"); + recoverTransferSettings(p); + recoverOpenRecovery(p); + recoverCacheSchema(p); + + if( bUseWrapper ) recoverUninstallWrapper(p); + }while( p->errCode==SQLITE_NOTADB + && (bUseWrapper--) + && SQLITE_OK==recoverOneStmt(p->dbIn, "ROLLBACK") + ); + } + + recoverLeaveMutex(); + recoverExec(p, p->dbOut, "BEGIN"); + recoverWriteSchema1(p); + p->eState = RECOVER_STATE_WRITING; + break; + } + + case RECOVER_STATE_WRITING: { + if( p->w1.pTbls==0 ){ + recoverWriteDataInit(p); + } + if( SQLITE_DONE==recoverWriteDataStep(p) ){ + recoverWriteDataCleanup(p); + if( p->zLostAndFound ){ + p->eState = RECOVER_STATE_LOSTANDFOUND1; + }else{ + p->eState = RECOVER_STATE_SCHEMA2; + } + } + break; + } + + case RECOVER_STATE_LOSTANDFOUND1: { + if( p->laf.pUsed==0 ){ + recoverLostAndFound1Init(p); + } + if( SQLITE_DONE==recoverLostAndFound1Step(p) ){ + p->eState = RECOVER_STATE_LOSTANDFOUND2; + } + break; + } + case RECOVER_STATE_LOSTANDFOUND2: { + if( p->laf.pAllAndParent==0 ){ + recoverLostAndFound2Init(p); + } + if( SQLITE_DONE==recoverLostAndFound2Step(p) ){ + p->eState = RECOVER_STATE_LOSTANDFOUND3; + } + break; + } + + case RECOVER_STATE_LOSTANDFOUND3: { + if( p->laf.pInsert==0 ){ + recoverLostAndFound3Init(p); + } + if( SQLITE_DONE==recoverLostAndFound3Step(p) ){ + p->eState = RECOVER_STATE_SCHEMA2; + } + break; + } + + case RECOVER_STATE_SCHEMA2: { + int rc = SQLITE_OK; + + recoverWriteSchema2(p); + p->eState = RECOVER_STATE_DONE; + + /* If no error has occurred, commit the write transaction on the output + ** database. Regardless of whether or not an error has occurred, make + ** an attempt to end the read transaction on the input database. */ + recoverExec(p, p->dbOut, "COMMIT"); + rc = recoverOneStmt(p->dbIn, "END"); + if( p->errCode==SQLITE_OK ) p->errCode = rc; + + recoverSqlCallback(p, "PRAGMA writable_schema = off"); + recoverSqlCallback(p, "COMMIT"); + p->eState = RECOVER_STATE_DONE; + recoverFinalCleanup(p); + break; + }; + + case RECOVER_STATE_DONE: { + /* no-op */ + break; + }; + } +} + + +/* +** This is a worker function that does the heavy lifting for both init +** functions: +** +** sqlite3_recover_init() +** sqlite3_recover_init_sql() +** +** All this function does is allocate space for the recover handle and +** take copies of the input parameters. All the real work is done within +** sqlite3_recover_run(). +*/ +sqlite3_recover *recoverInit( + sqlite3* db, + const char *zDb, + const char *zUri, /* Output URI for _recover_init() */ + int (*xSql)(void*, const char*),/* SQL callback for _recover_init_sql() */ + void *pSqlCtx /* Context arg for _recover_init_sql() */ +){ + sqlite3_recover *pRet = 0; + int nDb = 0; + int nUri = 0; + int nByte = 0; + + if( zDb==0 ){ zDb = "main"; } + + nDb = recoverStrlen(zDb); + nUri = recoverStrlen(zUri); + + nByte = sizeof(sqlite3_recover) + nDb+1 + nUri+1; + pRet = (sqlite3_recover*)sqlite3_malloc(nByte); + if( pRet ){ + memset(pRet, 0, nByte); + pRet->dbIn = db; + pRet->zDb = (char*)&pRet[1]; + pRet->zUri = &pRet->zDb[nDb+1]; + memcpy(pRet->zDb, zDb, nDb); + if( nUri>0 && zUri ) memcpy(pRet->zUri, zUri, nUri); + pRet->xSql = xSql; + pRet->pSqlCtx = pSqlCtx; + pRet->bRecoverRowid = RECOVER_ROWID_DEFAULT; + } + + return pRet; +} + +/* +** Initialize a recovery handle that creates a new database containing +** the recovered data. +*/ +sqlite3_recover *sqlite3_recover_init( + sqlite3* db, + const char *zDb, + const char *zUri +){ + return recoverInit(db, zDb, zUri, 0, 0); +} + +/* +** Initialize a recovery handle that returns recovered data in the +** form of SQL statements via a callback. +*/ +sqlite3_recover *sqlite3_recover_init_sql( + sqlite3* db, + const char *zDb, + int (*xSql)(void*, const char*), + void *pSqlCtx +){ + return recoverInit(db, zDb, 0, xSql, pSqlCtx); +} + +/* +** Return the handle error message, if any. +*/ +const char *sqlite3_recover_errmsg(sqlite3_recover *p){ + return (p && p->errCode!=SQLITE_NOMEM) ? p->zErrMsg : "out of memory"; +} + +/* +** Return the handle error code. +*/ +int sqlite3_recover_errcode(sqlite3_recover *p){ + return p ? p->errCode : SQLITE_NOMEM; +} + +/* +** Configure the handle. +*/ +int sqlite3_recover_config(sqlite3_recover *p, int op, void *pArg){ + int rc = SQLITE_OK; + if( p==0 ){ + rc = SQLITE_NOMEM; + }else if( p->eState!=RECOVER_STATE_INIT ){ + rc = SQLITE_MISUSE; + }else{ + switch( op ){ + case 789: + /* This undocumented magic configuration option is used to set the + ** name of the auxiliary database that is ATTACH-ed to the database + ** connection and used to hold state information during the + ** recovery process. This option is for debugging use only and + ** is subject to change or removal at any time. */ + sqlite3_free(p->zStateDb); + p->zStateDb = recoverMPrintf(p, "%s", (char*)pArg); + break; + + case SQLITE_RECOVER_LOST_AND_FOUND: { + const char *zArg = (const char*)pArg; + sqlite3_free(p->zLostAndFound); + if( zArg ){ + p->zLostAndFound = recoverMPrintf(p, "%s", zArg); + }else{ + p->zLostAndFound = 0; + } + break; + } + + case SQLITE_RECOVER_FREELIST_CORRUPT: + p->bFreelistCorrupt = *(int*)pArg; + break; + + case SQLITE_RECOVER_ROWIDS: + p->bRecoverRowid = *(int*)pArg; + break; + + case SQLITE_RECOVER_SLOWINDEXES: + p->bSlowIndexes = *(int*)pArg; + break; + + default: + rc = SQLITE_NOTFOUND; + break; + } + } + + return rc; +} + +/* +** Do a unit of work towards the recovery job. Return SQLITE_OK if +** no error has occurred but database recovery is not finished, SQLITE_DONE +** if database recovery has been successfully completed, or an SQLite +** error code if an error has occurred. +*/ +int sqlite3_recover_step(sqlite3_recover *p){ + if( p==0 ) return SQLITE_NOMEM; + if( p->errCode==SQLITE_OK ) recoverStep(p); + if( p->eState==RECOVER_STATE_DONE && p->errCode==SQLITE_OK ){ + return SQLITE_DONE; + } + return p->errCode; +} + +/* +** Do the configured recovery operation. Return SQLITE_OK if successful, or +** else an SQLite error code. +*/ +int sqlite3_recover_run(sqlite3_recover *p){ + while( SQLITE_OK==sqlite3_recover_step(p) ); + return sqlite3_recover_errcode(p); +} + + +/* +** Free all resources associated with the recover handle passed as the only +** argument. The results of using a handle with any sqlite3_recover_** +** API function after it has been passed to this function are undefined. +** +** A copy of the value returned by the first call made to sqlite3_recover_run() +** on this handle is returned, or SQLITE_OK if sqlite3_recover_run() has +** not been called on this handle. +*/ +int sqlite3_recover_finish(sqlite3_recover *p){ + int rc; + if( p==0 ){ + rc = SQLITE_NOMEM; + }else{ + recoverFinalCleanup(p); + if( p->bCloseTransaction && sqlite3_get_autocommit(p->dbIn)==0 ){ + rc = recoverOneStmt(p->dbIn, "END"); + if( p->errCode==SQLITE_OK ) p->errCode = rc; + } + rc = p->errCode; + sqlite3_free(p->zErrMsg); + sqlite3_free(p->zStateDb); + sqlite3_free(p->zLostAndFound); + sqlite3_free(p->pPage1Cache); + sqlite3_free(p); + } + return rc; +} + +#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */ diff --git a/codex-rs/state/vendor/sqlite-recover/sqlite3recover.h b/codex-rs/state/vendor/sqlite-recover/sqlite3recover.h new file mode 100644 index 0000000000..04f43482e2 --- /dev/null +++ b/codex-rs/state/vendor/sqlite-recover/sqlite3recover.h @@ -0,0 +1,249 @@ +/* +** 2022-08-27 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** +** This file contains the public interface to the "recover" extension - +** an SQLite extension designed to recover data from corrupted database +** files. +*/ + +/* +** OVERVIEW: +** +** To use the API to recover data from a corrupted database, an +** application: +** +** 1) Creates an sqlite3_recover handle by calling either +** sqlite3_recover_init() or sqlite3_recover_init_sql(). +** +** 2) Configures the new handle using one or more calls to +** sqlite3_recover_config(). +** +** 3) Executes the recovery by repeatedly calling sqlite3_recover_step() on +** the handle until it returns something other than SQLITE_OK. If it +** returns SQLITE_DONE, then the recovery operation completed without +** error. If it returns some other non-SQLITE_OK value, then an error +** has occurred. +** +** 4) Retrieves any error code and English language error message using the +** sqlite3_recover_errcode() and sqlite3_recover_errmsg() APIs, +** respectively. +** +** 5) Destroys the sqlite3_recover handle and frees all resources +** using sqlite3_recover_finish(). +** +** The application may abandon the recovery operation at any point +** before it is finished by passing the sqlite3_recover handle to +** sqlite3_recover_finish(). This is not an error, but the final state +** of the output database, or the results of running the partial script +** delivered to the SQL callback, are undefined. +*/ + +#ifndef _SQLITE_RECOVER_H +#define _SQLITE_RECOVER_H + +#include "sqlite3.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* +** An instance of the sqlite3_recover object represents a recovery +** operation in progress. +** +** Constructors: +** +** sqlite3_recover_init() +** sqlite3_recover_init_sql() +** +** Destructor: +** +** sqlite3_recover_finish() +** +** Methods: +** +** sqlite3_recover_config() +** sqlite3_recover_errcode() +** sqlite3_recover_errmsg() +** sqlite3_recover_run() +** sqlite3_recover_step() +*/ +typedef struct sqlite3_recover sqlite3_recover; + +/* +** These two APIs attempt to create and return a new sqlite3_recover object. +** In both cases the first two arguments identify the (possibly +** corrupt) database to recover data from. The first argument is an open +** database handle and the second the name of a database attached to that +** handle (i.e. "main", "temp" or the name of an attached database). +** +** If sqlite3_recover_init() is used to create the new sqlite3_recover +** handle, then data is recovered into a new database, identified by +** string parameter zUri. zUri may be an absolute or relative file path, +** or may be an SQLite URI. If the identified database file already exists, +** it is overwritten. +** +** If sqlite3_recover_init_sql() is invoked, then any recovered data will +** be returned to the user as a series of SQL statements. Executing these +** SQL statements results in the same database as would have been created +** had sqlite3_recover_init() been used. For each SQL statement in the +** output, the callback function passed as the third argument (xSql) is +** invoked once. The first parameter is a passed a copy of the fourth argument +** to this function (pCtx) as its first parameter, and a pointer to a +** nul-terminated buffer containing the SQL statement formated as UTF-8 as +** the second. If the xSql callback returns any value other than SQLITE_OK, +** then processing is immediately abandoned and the value returned used as +** the recover handle error code (see below). +** +** If an out-of-memory error occurs, NULL may be returned instead of +** a valid handle. In all other cases, it is the responsibility of the +** application to avoid resource leaks by ensuring that +** sqlite3_recover_finish() is called on all allocated handles. +*/ +sqlite3_recover *sqlite3_recover_init( + sqlite3* db, + const char *zDb, + const char *zUri +); +sqlite3_recover *sqlite3_recover_init_sql( + sqlite3* db, + const char *zDb, + int (*xSql)(void*, const char*), + void *pCtx +); + +/* +** Configure an sqlite3_recover object that has just been created using +** sqlite3_recover_init() or sqlite3_recover_init_sql(). This function +** may only be called before the first call to sqlite3_recover_step() +** or sqlite3_recover_run() on the object. +** +** The second argument passed to this function must be one of the +** SQLITE_RECOVER_* symbols defined below. Valid values for the third argument +** depend on the specific SQLITE_RECOVER_* symbol in use. +** +** SQLITE_OK is returned if the configuration operation was successful, +** or an SQLite error code otherwise. +*/ +int sqlite3_recover_config(sqlite3_recover*, int op, void *pArg); + +/* +** SQLITE_RECOVER_LOST_AND_FOUND: +** The pArg argument points to a string buffer containing the name +** of a "lost-and-found" table in the output database, or NULL. If +** the argument is non-NULL and the database contains seemingly +** valid pages that cannot be associated with any table in the +** recovered part of the schema, data is extracted from these +** pages to add to the lost-and-found table. +** +** SQLITE_RECOVER_FREELIST_CORRUPT: +** The pArg value must actually be a pointer to a value of type +** int containing value 0 or 1 cast as a (void*). If this option is set +** (argument is 1) and a lost-and-found table has been configured using +** SQLITE_RECOVER_LOST_AND_FOUND, then is assumed that the freelist is +** corrupt and an attempt is made to recover records from pages that +** appear to be linked into the freelist. Otherwise, pages on the freelist +** are ignored. Setting this option can recover more data from the +** database, but often ends up "recovering" deleted records. The default +** value is 0 (clear). +** +** SQLITE_RECOVER_ROWIDS: +** The pArg value must actually be a pointer to a value of type +** int containing value 0 or 1 cast as a (void*). If this option is set +** (argument is 1), then an attempt is made to recover rowid values +** that are not also INTEGER PRIMARY KEY values. If this option is +** clear, then new rowids are assigned to all recovered rows. The +** default value is 1 (set). +** +** SQLITE_RECOVER_SLOWINDEXES: +** The pArg value must actually be a pointer to a value of type +** int containing value 0 or 1 cast as a (void*). If this option is clear +** (argument is 0), then when creating an output database, the recover +** module creates and populates non-UNIQUE indexes right at the end of the +** recovery operation - after all recoverable data has been inserted +** into the new database. This is faster overall, but means that the +** final call to sqlite3_recover_step() for a recovery operation may +** be need to create a large number of indexes, which may be very slow. +** +** Or, if this option is set (argument is 1), then non-UNIQUE indexes +** are created in the output database before it is populated with +** recovered data. This is slower overall, but avoids the slow call +** to sqlite3_recover_step() at the end of the recovery operation. +** +** The default option value is 0. +*/ +#define SQLITE_RECOVER_LOST_AND_FOUND 1 +#define SQLITE_RECOVER_FREELIST_CORRUPT 2 +#define SQLITE_RECOVER_ROWIDS 3 +#define SQLITE_RECOVER_SLOWINDEXES 4 + +/* +** Perform a unit of work towards the recovery operation. This function +** must normally be called multiple times to complete database recovery. +** +** If no error occurs but the recovery operation is not completed, this +** function returns SQLITE_OK. If recovery has been completed successfully +** then SQLITE_DONE is returned. If an error has occurred, then an SQLite +** error code (e.g. SQLITE_IOERR or SQLITE_NOMEM) is returned. It is not +** considered an error if some or all of the data cannot be recovered +** due to database corruption. +** +** Once sqlite3_recover_step() has returned a value other than SQLITE_OK, +** all further such calls on the same recover handle are no-ops that return +** the same non-SQLITE_OK value. +*/ +int sqlite3_recover_step(sqlite3_recover*); + +/* +** Run the recovery operation to completion. Return SQLITE_OK if successful, +** or an SQLite error code otherwise. Calling this function is the same +** as executing: +** +** while( SQLITE_OK==sqlite3_recover_step(p) ); +** return sqlite3_recover_errcode(p); +*/ +int sqlite3_recover_run(sqlite3_recover*); + +/* +** If an error has been encountered during a prior call to +** sqlite3_recover_step(), then this function attempts to return a +** pointer to a buffer containing an English language explanation of +** the error. If no error message is available, or if an out-of memory +** error occurs while attempting to allocate a buffer in which to format +** the error message, NULL is returned. +** +** The returned buffer remains valid until the sqlite3_recover handle is +** destroyed using sqlite3_recover_finish(). +*/ +const char *sqlite3_recover_errmsg(sqlite3_recover*); + +/* +** If this function is called on an sqlite3_recover handle after +** an error occurs, an SQLite error code is returned. Otherwise, SQLITE_OK. +*/ +int sqlite3_recover_errcode(sqlite3_recover*); + +/* +** Clean up a recovery object created by a call to sqlite3_recover_init(). +** The results of using a recovery object with any API after it has been +** passed to this function are undefined. +** +** This function returns the same value as sqlite3_recover_errcode(). +*/ +int sqlite3_recover_finish(sqlite3_recover*); + + +#ifdef __cplusplus +} /* end of the 'extern "C"' block */ +#endif + +#endif /* ifndef _SQLITE_RECOVER_H */